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INSY 3800 Final Exam
Ch 20-29, 36-39
416
Engineering
Undergraduate 3
12/02/2010

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Term
Adhesive bonding (470)
Definition
attractive means of joining the various layers and can be applied to both metallic and nonmetallic materials. The lamination of polymer matrix composites often utilizes films of unpolymerized resin that are introduced between the layers. Pressing at elevated temperature then cures the resin and completes the load
Term
Annealing (467)
Definition
in dealing with tempered glass, this can be used to reduce unfavorable residual stresses that might lead to cracking
Term
Autoclave (474)
Definition
Higher heats and pressures can be used when the part is cured in this, which limits the size of the product. The supporting molds and vacuum-bagged layups are placed inside a heated pressure vessel where curing occurs under elevated temperatures and pressures in the range 0.4 to 0.7 MPa (50 to 100 psi).
Term
Blow molding (467)
Definition
used to convert resins into bottles and other hollow shape containers
Term
Braiding (476)
Definition
To overcome failures in laminar-type composites such as interlaminar cracking and delamination upon impact, high strength reinforcing fibers can also be interwoven into 3D performs by processes that include weaving, stitching and ____ though the thickness of stacked 2D performs
Term
Bulk-Molding Compound (475
Definition
fiber reinforced materials where short fibers are distributed in random orientation
Term
Calendering (461)
Definition
In the ____ process, a mass of dough-like thermoplastic is forced between and over two or more counterrotating rolls to produce thin sheets or films of polymer, which are then cooled to induce hardening
Term
Casting (455)
Definition
This is the simplest of the shape forming processes because no fillers are used and no pressure is required.The thermoplastic polymer is simply melted and the liquid is poured into a container having the shape of the desired part
Term
Cementation (469
Definition
This is an alternative method of producing strength that does not require elevated temperature. A liquid binder material is used to coat the ceramic particles, and a subsequent chemical reaction converts the liquid to a solid, forming strong, rigid bonds
Term
Ceramics (467)
Definition
The fabrication processes applied to ____ materials generally fall into 2 distinct classes, based on the properties of the material: glasses if the material can be shaped by means of viscous flow, or crystalline ____ if the material is hard and brittle, with high melting points
Term
Ceramic-matrix Composites (477)
Definition
Unlike polymeric or metal-matrix composites, where failures originate in or along the reinforcement fibers, _____ often fail due to flaws in the matrix. If the reinforcement is bonded strongly to the matrix, a matrix crack will propagate right through to the fibers.
Term
Clay Products (468)
Definition
These are based on special types of ceramics blended with water and various additives to produce a material that can be shaped by most of the traditional forming methods
Term
Cold Molding 458
Definition
this, the uncured thermosetting material is pressed to shape while cold and is then removed from the mold and cured in a separate oven.
Term
Composites 470
Definition
engineered materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct on a macroscopic level within the finished structure
Term
Compression Molding 475
Definition
When production quantities are large and quality needs to be high, matched metal dies can be substituted for the mold and bag, the process then becomes a modification of this. In this, a sheet-molding compound, bulk-molding compound, or a preformed mat is placed on the press, and heat and pressure are applied.
Term
Crystalline Ceramics 467
Definition
have a characteristically brittle behavior and are normally manufactured into useful components; cannot be formed by techniques requiring either plasticity or melting. processed in the solid state by techniques that utilize particles or aggregates and resemble those used in powder metallurgy.
Term
Devitrification -
Definition
a special heat treatment that controls the nucleation and growth of the crystalline component, used to fabricate glass ceramics.
Term
Dipping 465 –
Definition
process used to produce relatively thin parts with uniform wall thickness, such as boots, gloves, and fairings. The simplest fabrication process for rubbers and elastomers.
Term
Dry Pressing 467
Definition
used in the fabrication of crystalline ceramics, this is a common technique that enables dry powders to be pressed into useful shapes
Term
Elastomer 455
Definition
A material that behaves like rubber but is made from synthetic polymers and is superior to rubber in several mechanical or chemical properties.
Term
Explosive Bonding 470 –
Definition
his is another practical means of bonding layers of metals. In this a piece of explosive material progressively detonates above layers to be be joined, causing a pressure wave to sweep across the interface
Term
Extrusion 466
Definition
Products such as inner tubes, graden hoses, tubing and strip moldings (long plastic products with uniform cross sections) can be produced by this, where a compounded material is forced through a die by a screw device similar to that described for plastics.
Term
Fibers
Definition
used to reinforce composites; these are embedded in a selected matrix with the proper alignment and spacing to produce the desired properties. Can be continuous or discontinuous.
Term
Filament winding 476 -
Definition
s a fabrication technique for creating composite material structures. The process involves winding filaments under varying amounts of tension over a male mould or mandrel. The mandrel rotates while a carriage moves horizontally, laying down fibers in the desired pattern.
Term
Firing 468
Definition
his is a subsequent heating process; slurry –type materials must first be dried in a controlled manner that is designed to control dimensional changes and minimize stresses. The material is then heated to temperatures between .5 to .8 times the absolute melting point. AKA sintering
Term
Foam Molding 461 –
Definition
in this, a foaming agent is mixed with the plastic resin and releases gas or volatilizes when the material is heated during molding
Term
Glass 467
Definition
Glass can be manufactured into useful articles by first heating the material to produce a molten or viscous state, shaping the material by means of viscous flow, and then cooling the material to produce a solid product. Typically brittle, and optically transparent.
Term
Glass Ceramic 467
Definition
part crystalline, part glass
Term
Hand Layup 475
Definition
the layers of pliable resin coated cloth are placed in an open mold or draped over a form
Term
Hot-isostatic Pressing 467
Definition
common technique in fabricating crystalline ceramics because crystalline ceramics cannot be formed by techniques requiring either plasticity or melting. Exhibit features and limitations similar to those discussed in ch 16.
Term
Injection Molding 466 - I
Definition
Injection molding of fiber-reinforced plastics is a process that competes with metal die castings and offers comparable properties at considerably reduced weight. In the simplest variation, chopped or continuous fibers are placed in a mold cavity that is then closed and injected with resin.
Term
Inserts 464
Definition
metal, often incorporated into plastic products to provide enhanced performance or unique features. Can be used to provide threaded cavities, holes, and alignment pins in plastic parts.
Term
Isostatic Pressing 467
Definition
used in fabricating crystalline ceramics. Exhibits features and limitations similar to those discussed in ch 16.
Term
Lamination 473 -
Definition
prepregs, mats, or tapes are stacked to produce a desired thickness and cured under pressure and heat. Resulting products possess unusually high strength properties as a result of the integral fiber reinforcement.
Term
Laser sintering 469
Definition
(laser molting) Prototypes or small production quantities of ceramic products have also been made by the laser sintering of ceramic powders. Parts are made by building up successive layers of material by laser sintering of thin layers of heat-fusible powder. For ceramic parts, the polymer coating on the powder is bonded by the laser.
Term
Mats 473
Definition
stacked to produce a desired thickness and cured under pressure and heat in the lamination process.
Term
Metal-matrix Composites
Definition
is composite material with at least two constituent parts, one being a metal. The other material may be a different metal or another material, such as a ceramic or organic compound. When at least three materials are present, it is called a hybrid composite. An MMC is complementary to a cermet.
Term
Open-mold processing 475
Definition
Where the layers of liable resin-coated cloth are simply placed in an open mold or draped over a form.
Term
Parison 456
Definition
A round, solid-bottom, hollow-tube preform. It is made from heated plastic by either extrusion or injection molding.
Term
Plastics 454
Definition
Is shown to be substantially different from metals in both structure and properties. Tends to be used closer to their design limits, and many fabrication processes convert the raw plastic into a finished product on a single operation.
Term
Prepregs 472-4
Definition
Involves the formation of a woven fabric that has been infiltrated with a matrix material.
Term
Pressure-bag molding
Definition
A flexible membrane is positioned over the female mold cavity and pressurized to force the individual plies together and drive out entrapped air and excess resin.
Term
Pultrusion 472, 476 -
Definition
A continuous process that is used to produce relatively simple shapes of uniform cross section, such as round, rectangular, tubular, plate, sheet, and structural products.
Term
Reaction injection molding 455 459 - P
Definition
Process, in which two or more liquid monomers are metered into a unit where they are intimately mixed by the impingement of liquid streams that have been pressurized to a value between 13 and 20 MPa (2000 and 3000 psi).
Term
Resin-Transfer molding
Definition
In RTM the resin is injected or drawn into a mold, which contains the fibres, from a homogeniser under low pressure.
Term
Roll bonding 477 -
Definition
sheets of materials are passed thru rolls of a rolling mill
Term
Rotational molding 455 460 -
Definition
used to produce hollow, seamless products of a wide variety of shapes and sizes
Term
Rovings
Definition
(couldn't find in the book - from dictionary) a slightly twisted roll or strand of usually textile fibers
Term
Sandwich structures 470
Definition
- In ____ such as corrugated cardboard or the honeycomb shown in Figure 20-19, thin layers of facing material are bonded, usually by adhesive to a lightweight filler material.
Term
Sheet-molding compound 457 475 -
Definition
Bulk compound molding compound, or preformed mat is placed on the press, and heat and pressure are applied. Temps usually range from 110-160 F and pressures from 1-7 MPa. With heated dies, the thermoset curing occurs during the compression operation, and cycles range from 1 to 5 minutes.
Term
Sintering 468 -
Definition
The processes described previously can all be used to produce useful shapes from ceremic materials, but useful strength generally requires a subsequent hearing operation known as firing or ____.
Term
Slip Casting 468 -
Definition
ceramic powder is mixed with a liquid to form slurry
Term
Spinning 461 -
Definition
Filaments, fibers, and yarns can be produced by spinning, a modified form of extrusion. Molten thermoplastic polymer is forced through a die containing many small holes. Where multi-strand yarns or cables are desired, the dies can rotate or spin to produce the twists and wraps.
Term
Spray molding 476 -
Definition
used when continuous or woven fibers are not required to produce the desired properties. Produced by mixing chopped fivers and resin and spraying onto a mold
Term
Tapes 473
Definition
In the lamination process, prepregs, mats or _____ are stacked to produce a desired thickness and cured under pressure and heat
Term
Tempered glass 467 -
Definition
Glass created through special heat treatments. Applying forced cooling to the exposed surfaces, a residual stress pattern of surface compression can be induced creating tempered glass. This glass is stronger and more fracture resistant, since cracks tend to initiate on free surfaces.
Term
Thermoforming 460
Definition
thermoplastic sheet material is heated to a working temperature and then formed into a finished shape by heat, pressure, or vacuum.
Term
Thermoplastic polymer 455 -
Definition
These can be heated to produce either a soft, formable solid or a liquid. The polymerized material can then be cast, injected into a mold, or forced into or through dies to produce a desired shape.
Term
Tows 471 -
Definition
Untwisted assemblies of fibers.
Term
Transfer Molding 457 -
Definition
Is sometimes used to reduce the turbulence and uneven flow that can result from the high pressures of hot-compression molding. Transfer molding combines elements of both compression molding and injection molding and enables some of the advantages of injection molding to be utilized with thermosetting polymers.
Term
Vacuum-bag molding 474 - I
Definition
In this process, air pressure holds the laminate against the mold while the resin cures (curing generally occurs at room temperature).
Term
Viscous Flow 467 -
Definition
Process of shaping material at a molten state (glass in this case).
Term
Vitrification (internet) -
Definition
The transition of a substance into glass.
Term
Yarns 471 -
Definition
Twisted assemblies of filaments.
Term
Aluminum Oxide (528)
Definition
Ceramics are made of pure aluminum oxide. Used as a metallic binder.
Term
BUE (built up edge) (512, 528)
Definition
variation of continuous chip, the hight temp/pressure cutting zone causes the work material to adhere or weld to the cutting edge of the tool forming a _______
Term
Carbides (524, 526)
Definition
nonferrous alloys
Term
Cast Cobalt Alloy(515, 523)
Definition
AKA stellite tools, cobalt rich, chromium-tungsten-cast-alloys having properties between High speed steel and cemented carbides
Term
Cermets (528)
Definition
ceramic material in a metal binder
Term
Chemical Vapor Deposition(CVD)(520)
Definition
atmosphere controlled process in the range of 950 to 1050 Celcius
Term
Crater wear
Definition
wear on the rake face of the tool Think of wearing on the threads of a screw.
Term
cutting tools materials
Definition
directly influence the productive of the machining operation ie. the hardness of the material to be cut, the speed of the cut......
Term
(DLC) Depth of cut line
Definition
is the depth the tool must travel trough the material this will effect the life of the tool and the time it takes to complete the task
Term
Diamonds
Definition
The hard material known. Man made diamonds are used as tools in machining very hard metals
Term
(HSS) Hot hardness steel
Definition
the ability of a steel to withstand high temperatures with out loosing its hardens. This is very attractive in tools that cut extremely hard materials
Term
Machinability
Definition
refers to the ease with which a metal can be machined to an acceptable surface finish. The principal definitions are based on material properties, tool life, and cutting speed.
Term
Physical vapor deposition (PVD)(520)
Definition
an effective coating process for improving the life and performance of tools, used on about 15-20% of all tool steels. The three methods (preformed under a hard vacuum) in use are reactive sputtering, reactive ion plating, and arc evaporation.
Term
Polycrystalline diamond tools(530)
Definition
consists of a thin layer of diamond particles sintered together and metallurgically bonded to a cemented carbide substrate.
Term
Single-crystal diamonds(530)
Definition
used for precision machining of large mirrors. Also used to machine brass watch faces, and slice biological materials to view under microscopes.
Term
Sintered
Definition
also called cemented are carbides because they are manufactured by powder metallurgy techniques.
Term
Stellite
Definition
(523) also called cast cobalt alloys are cobalt rich, chromium-tungsten-carbon cast alloys and retain their hardness at high temperatures, so they can be used at higher cutting speeds.
Term
Titanium nitride(518)
Definition
the coating used in PVD and is formed by reacting free titanium ions with nitrogen away from the surface of the tool and using physical means to transport the coating
Term
Wear land
Definition
couldn't find this term
Term
Back Rake Angle
Definition
The angle that the tool makes with respect to a vertical from the workpiece.
Term
Boring
Definition
process of enlarging a hole that has already been drilled.
Term
Broaching
Definition
In this the cutting tool moves into the work while the work remains stationary. This operation uses a teethed tool to do work.
Term
Chatter
Definition
A self-excited vibration that is caused by the closed-loop force-displacement response of the machining process.
Term
Built-up Edge
Definition
a formation on the cutting tool, is associated with a variation of the continuous chip, often encountered in machining ductile materials.
Term
Chip Ratio
Definition
can be determined dynamically if a reliable means to measure Vc can be found.
Term
Chip Velocity
Definition
the velocity of the chip being sheared.
Term
Cutting Stiffness
Definition
This is a material property related to shear flow stress, hardness and work hardening and is often described in a relative sense of the machinability of materials.
Term
Cutting Tool
Definition
are mounted in machine tools, which provide the required movement of the tool with respect to the work (or vice versa) to accomplish the process desired.
Term
Depth of Cut (DOC)
Definition
_________ is the distance the tool has plunged into the surface. ______=(D1-D2)/2 D1:initial diameter, D2:final diameter
Term
Drilling
Definition
is a cutting process that uses a bit to cut or enlarge a hole in solid materials. It cuts by applying pressure and rotation to the workpiece, which forms chips at the cutting edge.
Term
Feed
Definition
amount of material removed per revolution or per pass of the tool over the workpiece
Term
Friction Force
Definition
Force resisting the relative movement. Gets stronger with increased surface area, and/or pressure.
Term
Grinding (Abrasive Machining)
Definition
Using a rough(abrasive) grinding wheel to cut away at metal. Usually only useful for shallow cuts and finishing.
Term
Machine Tool
Definition
powered mechanical device used to fabricate metal components of by selective removal of metal.
Term
Milling
Definition
_________ moves the workpiece radially against the rotating cutter, which cuts on its sides as well as its tip.
Term
Oblique Machining
Definition
In _______ machining, the cutting edge and cutting motion are not perpendicular to each other.
Term
Orthogonal machining
Definition
done to test machining mechanics and theory. Is the measurement of two forces and can be obtained in laboratory practice by: machining a plate, end cutting a tube wall in a turning setup, and end cutting a plate feeding in a facing direction.
Term
Sawing
Definition
one of the seven basic chip formation processes.
Term
Self-excited vibration
Definition
the periodic response of the system to a constant input. The vibrations may grow in amplitude (become unstable) and occurs near the natural frequency of the system regardless of the input.
Term
Shaping
Definition
where the cutting edge and the cutting motion are not perpendicular to each other.
Term
shear angles
Definition
The onset of the shear process takes place along the lower boundary of the shear zone defined by this?
Term
shear velocity
Definition
can be found by using sophisticated electronics and slow-motion playback.
Term
Shear Strain
Definition
Also known as shear. A deformation of a solid body in which a plane in the body is displaced parallel to itself relative to parallel planes in the body; quantitatively, it is the displacement of any plane relative to a second plane, divided by the perpendicular distance between planes. The force causing such deformation.
Term
Shear force (flow stress)
Definition
External force that acts parallel to a plane, unlike compressive force and tensile force which act perpendicularly.
Term
Specific horsepower(493)
Definition
Specific horsepower is also known as the unit horese power (hp/lb/hr)
Term
speed(507)
Definition
the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity.
Term
stability lobe diagram
Definition
a plot that separates unstable combinations of chip width, or axial depth of cut in peripheral end milling, and spindle speed (i.e., those that produce chatter) from stable combinations.
Term
turning
Definition
Shaping a member on a lathe.
Term
vibration(504)
Definition
A continuing periodic change in a displacement with respect to a fixed reference. This is the mechanism by which a process dissipates energy. Also called chatter.
Term
workholding device
Definition
A device used to locate and hold a workpiece. The workholding device references the tool performing the operation on the part being held.
Term
workpiece
Definition
An object being worked on with a tool or machine.
Term
Milling
Definition
a basic machining process by which a surface is generated by progressive chip removal
Term
milling cutter
Definition
the cutting tool used in milling is known as a _____
Term
interrupted cutting
Definition
when equally spaced peripheral teeth intermittently engage and machine the workpiece
Term
peripheral milling
Definition
the surface is generated by teeth located on the periphery of the cutter body. The surface is parallel with the axis of rotation of the cutter
Term
slab milling
Definition
usually performed on horizontal milling machines. The tool rotates at some rpm while the work feeds past the tool at a table feed rate in inches per minute
Term
face milling
Definition
done on both horizontal and vertical spindle machines
Term
end milling
Definition
very common operation performed on both vertical and horizontal spindle milling machines or machining centers
Term
up milling
Definition
the traditional way to mill, AKA conventional milling. The cutter rotates against the direction of feed of the workpiece
Term
climb (down) milling
Definition
the cutter rotation is in the same direction as the feed rate
Term
staggered-tooth milling cutter
Definition
narrow cylindrical cutters having staggered teeth, and with alternate teeth having opposite helix angles
Term
straddle milling
Definition
two or more side milling cutters often are spaced on an arbor to straddle the workpiece
Term
Woodruff keyseat cutters
Definition
made for the purpose of milling the semi-cylindrical seats required in shafts for woodruff keys...they also come in standard woodruff key sizes
Term
column-and-knee milling
Definition
the column mounted on the base, is the main supporting frame for all the other parts and contains the spindle with is driving mechanism
Term
profilers
Definition
milling machines that can duplicate external or internal geometries in two dimensions
Term
duplicators
Definition
produce forms in 3 dimensions
Term
fixtures
Definition
designed to specifically hold a part in the correct location with respect to the tool. They also reduce the time it takes to put the part in the machine...provide clamping forces that counteract the cutting forces
Term
saddle
Definition
the load (?)
Term
drilling
Definition
holes are made by doing this
Term
twist drills
Definition
most common type of drill with 3 parts: body, point, and shank
Term
flutes
Definition
contained in the body, spiral or helical grooves that are separated by lands
Term
helix angle
Definition
Principal rake angles behind the cutting edges are formed by the relation of the flute ________ to the work
Term
web
Definition
the thin ______ between the flutes that forms a metal column or backbone
Term
chisel end
Definition
the intersection of the web and cone produces this
Term
tang
Definition
at the end of the taper shank, fits loosely in a slot at the end of the tapered hole in the spindle
Term
deep-hole drills
Definition
AKA gun drills, used when deep holes are to be drilled
Term
gundrill
Definition
half-round drills, drilled axially with a coolant hole to deliver cutting fluids to the cutting edge
Term
trepanning gundrill
Definition
leaves a solid core
Term
spade drills
Definition
widely used for making holes 1in or larger in diameter at low speeds, or with high-feeds
Term
indexable insert drills
Definition
can produce a hole four times faster than a spade drill because they run at high speeds/low feeds and are really more of a boring process than a drilling process
Term
chuck
Definition
holds straight-shank drills, are adjustable over a considerable size range and have radial steel fingers
Term
jigs
Definition
Work that is to be drilled is held in a vise or in specially designed workholders called _____
Term
drill press
Definition
the common name for the machine tool used for drilling. consists of a base, a column that supports a pwerhead, a spindle, and a worktable
Term
gang-drilling machines
Definition
used when several related operations, such as drilling holes of different sizes, reamin, or counterboring, must be done on a single part
Term
turret drilling machines
Definition
used when a series of holes of different sizes, or a series of operations must be done repeatedly in succession
Term
radial drilling machine tools
Definition
used on large workpieces that cannot easily be handled manually. These machines have a large, heavy, round vertical column supported by a base
Term
multiple spindle drilling machines
Definition
mass-production machines with as many as 50 spindles driven by a single powerhead and fed simultaneously into the work
Term
counterboring
Definition
provides an enlarged cylindrical hole with a flat bottom so that a bolt-head, or a nut, will have a smooth bearing surface that is normal to the axis of the hole
Term
countersinking
Definition
makes a beveled section at the end of a drilled hole to provide a proper seat for a flat -head screw or rivet
Term
spot facing
Definition
doen to provide a smooth bearing area on an otherwise rough surface at the opening of a hole and normal to its axis
Term
hand reamers
Definition
intended to be turned and fed by hand and to remove only a few thousandths of an inch of metal
Term
machine reamers
Definition
for use with various machine tools ar slow speeds. These reamers also have chamfers on the front end of the cutting edges
Term
shell reamers
Definition
used for sizes over 3/4 in. in order to save cutting tool material
Term
thrust force
Definition
push something else backwards (usually friction or normal force) to accelerate yourself forwards
Term
Apron
Definition
together with the ____, provides the means for mounting and moving cutting tools. Is a part of the carriage assembly.
Term
Bed
Definition
is the base and backbone of a lathe. Is usually made of well normalized or aged gray or nodular cast iron and provides a heavy, rigid frame on which all the other basic components are mounted.
Term
Boring
Definition
Always involve the enlarging of an existing hole, which may have been made by a drill or may be the result of a core in a casting. Essentially, ______ is internal turning. _____ can use single-point cutting tools to produce internal cylindrical or conical surfaces.
Term
Carriage
Definition
a relatively flat H-shaped casting, rides on the outer set of ways on the bed. It is on the carriage assembly which provides the mean for mounting and moving cutting tools.
Term
Chucks
Definition
A lathe chuck is a device on the driven spindle on the head (headstock) of the machine that holds the workpiece. It grips and spins it.
Term
Collets
Definition
is a holding device, specifically, a subtype of a chuck that forms a collar around the object to be held and exerts a strong clamping force on the object when it is tightened via a tapered outer collar. It may be used to hold a workpiece or a tool.
Term
Cutoff
Definition
When the tool is fed all the way to the axis of the workpiece, it will be cut in two. Also known as parting.
Term
Cutting Tools
Definition
p 572 Most lathe operations are done using single point ____, such as those illustrated in Figure 23-25. On right-hand (and left-hand turning) and facing tools, the ____ usually takes place on the side of the tool; therefore, the side rake angle is of primary importance, particularly when deep cuts are made.
Term
Depth of cut
Definition
p550 Roughing cuts may be as heavy as proper chip thickness, cutting dynamics, tool life, lathe horsepower, and the workpiece permit. Large _______ and smaller feeds are preferred to the reverse procedure, because fewer cuts are required and less time is lost in reversing the carriage and resetting the tool for the following cut.
Term
Drilling
Definition
p553 This can be done on lathes with the ____ mounted in the tailstock quill of engine lathes or the turret on turret lathes and fed against a rotating workpiece.
Term
Engine Lathe
Definition
p556 The essential components of an _____ are the bed, headstock assembly, tailstock assembly, carriage assembly, quick-change gearbox, and the leadscrew feed rod.
Term
Face Plates
Definition
p579 These are used to support irregularly shaped work that cannot be gripped easily in chuck or collets. The work can be bolted or clamped directly on the ____ or can be supported on an auxiliary fixture that is attached to the _____.
Term
Facing
Definition
An operation called _________ is when the tool is fed at 90 degrees to the axis of rotation, using a tool that is wider than the width of the cut producing a flat surface
Term
Feed
Definition
p 585 The ___, fr, is given in inches per revolution. The depth of cut in drilling is equal to half the ____ rate, or t = fr/2. The ___ rate in inches per minute fm, is frN. In dealing with drilling, because the ___ may be manually controlled, care must be exercised, particularly in drilling small holes.
Term
Follow Rest
Definition
p 580 This is bolted to the lathe carriage. It has two contact fingers that are adjusted to bear against the workpiece, opposite the cutting tool, in order to prevent the work from being deflected away from the cutting tool by the cutting forces.
Term
Headstock
Definition
this is mounted in a fixed position on the inner ways of a lathe and provides powered means to rotate the work at various rpm values.
Term
Knurling
Definition
This produces a regularly shaped, roughened surface on a workpiece. In most cases this is done on external cylindrical surfaces using lathes; it is a chipless, cold forming process
Term
Lathe center
Definition
Workpieces that are relatively long with respect to their diameters are usually machined between __________. Two of these are used, one in the spindle hole and one in the hole in the tailstock quill. Two types are used, called dead and live
Term
Mandrels
Definition
Workpieces that must be machined on both ends or are disk-shaped are often mounted on ______________ for turning between centers. There are three common types: Gang, Solid, and Cone.
Term
Metal Removal Plate
Definition
This controls the trimmings and shavings that are created in turning and boring processes
Term
Milling
Definition
This can be done on a lathe but requires special attachments; it is the basic machining process by which a surface is generated by progressive chip removal. The act or process of grinding, cutting, pressing, or crushing
Term
Parting
Definition
this is the operation by which one section of a workpiece is severed from the remainder by means of a cutoff tool; If the tool is fed all the way to the axis of the workpiece, it will be cut in two. This is called ____________ or cuttoff and a simple, thin tool is used
Term
Quill
Definition
This is a hollow steel cylinder, usually about 2 to 3 inches in diameter that can be moved longitudinally in and out of the upper casting by means of a handwheel and screw.
Term
Reaming
Definition
on a lathe involves no special precaution. To enlarge to desired size by means of a reamer.
Term
Screw Machine
Definition
are lathes designed for completely automatic operations.
Term
Steady Rest
Definition
provide means for supporting such work between the headstock and the tailstock. Can also be used in place of the tailstock as a means of supporting the end of long pieces, pieces having too large an internal hole to permit using a regular dead center, or work where the end must be open for boring.
Term
Tailstock
Definition
assembly containing three parts, a lower casting fits on the inner ways of the bed, an upper casting fits on the lower one, and the third major component of the assembly is the tailstock quill.
Term
Taper Turning
Definition
when the tool is fed at an angle to axis of rotation and an external conical surface results.
Term
Turning
Definition
constitutes the majority of the lathe work and is the process of machining external cylindrical and conical surfaces.
Term
Turret Lathe
Definition
a longitudinally feedable, hexagon turret replaces the tailstock and the turret on which six tools can be mounted can be rotated about a vertical axis to bring each tool into operating position, and the entire unit can be translated parallel to ways.
Term
Workholding
Definition
devices for lathes that are commonly used for supporting work pieces.
Term
Ablate
Definition
to remove chemically
Term
Abrasive flow machining
Definition
involves the use of a semisolid liquid or gel laden with abrasives to flow over or through a workpiece to perform edge finishing, deburring, radiusing, polishing, or minor surface machining.
Term
Abrasive jet machining
Definition
removes material by a focused jet of abrasives and is similar in many respects to AWC with the exception that momentum is transferred to the abrasive particles by a jet of inert gas.
Term
Abrasive waterjet cutting
Definition
is where abrasives are added to the waterjet in a mixing chamber on the dowstream side of the waterjet orifice.
Term
Anisotropy
Definition
(also sometimes referred to as etch factor) is used to describe the directionality of the cut. The _____________, A, of a material/etchant interaction in photochemical machining is defined as: A = d/U
Term
Chemical blanking
Definition
Through-etching of the workpiece. Typically performed using double-sided etching to increase production rates and minimize taper on the etched walls of the feature.
Term
Chemical machining (CHM)
Definition
simplest and oldest of the chipless machining processes. Process of removing material from a workpiece by selectively exposing it to a chemical reagent or etchant. The mechanism for metal removal is the chemical reaction between the etchant and the workpiece resulting in dissolution of the workpiece.
Term
Chemical-mechanical polishing
Definition
uses the synergy of chemistry and mechanical grinding to obtain flatness on the order of 50 nm.
Term
Chemical milling-
Definition
The gross removal of material from a body by the corrosive action of an acid or an alkali that results in a substantial change of shape of the body.
Term
cut-and-peel-
Definition
simplest method of applying a maskant applied to the entire surface of the workpiece by dipping or spraying. Once the coating dries, it is then selectively removed in those areas where etching is desired by scribing he maskant with a knife and peeling away the unwanted portions.
Term
dimer-
Definition
a chemical entity consisting of two structurally similar subunits called monomers joined by bonds that can be either strong or weak.
Term
dishing-
Definition
thinning in center due to improper agitation or stacking of parts in tank
Term
duty cycle-
Definition
the on-time as a percentage of the total cycle time (inverse of the frequency)
Term
electrical discharge machining-
Definition
process removes metal by discharging electric current from a pulsating DC power supply across a thin interelectrode gap between the tool and the workpiece.
Term
electrical discharge wire cutting-
Definition
in this, the electrode is a wire used for cutting through-cut features driving the workpiece with a CNC table.
Term
electrochemical deburring-
Definition
a deburring process which works on the principal that electrolysis is accelerated in areas with small interelectrode gaps and prevented in areas with insulation between electrodes.
Term
Electrochemical grinding (ECG)
Definition
while the product is rotated low voltage high current used to remove some of the material the rest of the affected material is oxidized the oxidized material is then ground away
Term
Electrochemical machining (EM)
Definition
using high velocity stream of charged particles through a glass tube used to remove unwanted material
Term
Electrochemical micromachining
Definition
Removes material by anodic dissolution with a rapid flowing electrolyte uses electrical current to bring about chemical change
Term
Electrochemical polishing
Definition
low current density the charged particles are forced through a glass tube used to remove unwanted material at a slow rate fine finish
Term
Electron beam machining
Definition
A thermal process that uses a beam of high energy that vaporises the metal tat is to be removed
Term
Electropolishing
Definition
low current density the charged particles are forced into wok piece with out a part specified had tool to remove unwanted material at a slow rate gives a fine finish
Term
Electrostream drilling
Definition
using high velocity stream of charged particles through a glass tube used to drill holes usually multiple small holes at one time
Term
Etch Factor/Etch Radius
Definition
Something to consider in chemical machining. Etch Factor (E) describes the relationship between undercut (U) and depth of cut (d). See picture.
Term
Fine Plasma Cutting/High-definition Plasma/Precision PAC
Definition
Uses a special nozzle to stabilize the plasma pressure for a more finely defined PAC beam. Reduces problems of HAZ and dross on the bottom of parts.
Term
Gel Milling
Definition
CHM where the etchant is applied in a gel form.
Term
Heat-affected zone(HAZ)
Definition
In PAC(plasma arc cutting), the ____________ is a negative side-effect. (Not from book, this is just an inference) This makes it unusable where the workpiece is thermally delicate/sensitive.
Term
Hydrodynamic(Waterjet) Machining
Definition
uses a high-velocity fluid jet to perform a slitting operation. Water is ejected from a nozzle at very high pressure (up to 60,000 psi).
Term
Intergranular Attack
Definition
Preferential etching due to ______________ can also be an issue in Chemical Machining.
Term
Ion beam machining(IBM)
Definition
Nano-scale machining used to cleave wafers. Often used on defective wafers for characterization and failure analysis.
Term
Photochemical milling (689)
Definition
Milling using the photoresist method of applying maskants. Named photochemical because its earliest usage was for replacing mechanical miling on large componets. It is often used to remove weight on on aircraft componets (see fig 28-4)
Term
Photoresists (688)
Definition
The most common and precise method for creating maskants involves using UV light sensitive emulsions called _____
Term
Pitting (689)
Definition
A defect due to unequal etch rates
Term
Plasma Arc Cutting (PAC) (714)
Definition
Uses a superheated stream of electrically ionized gas to melt and remove material. 20,000 to 50,000 deg F.plasma is created inside a water cooled nozzle by electrially ionzing a suitable gas such as nitrogen, hydrogen, argon, or mixtures of these gases. The process can be used on almost any conductive metal.
Term
Precision PAC (715)
Definition
uses a special nozzle where either a high flow vortex or a magnetic field causes the plasma to spin rapidly and stabilizes the plasma pressure. The fast spinning plasma results in a finely defined beam that cuts a narrow kerf with a perpendicular edge
Term
Pulsed-Current ECM (696)
Definition
high current densities (> 100 A/cmsq) are pulsed on for durations. The relaxation interval permits reaction byproducts to be removed from the interelectrode gap at low electrolyte flow rates without electrolytic desposition on the ECM tool.
Term
Ram EDM (706, 709)
Definition
One of the two dfferent types of EDM based on the shape of the tool electrode used. In ____ the electrode is a die in the shape of the negative of the cavity to be produced in bulk material. By feeding the die into the workpiece, the shape of the die is machined into the workpiece
Term
Screen Printing (688)
Definition
a method of applying maskants that utilizes traditional sik-screen technology
Term
Water jet Cutting (WJC) (701)
Definition
uses a high- velocity fluid jet impinging on the workpiece to perform a slitting operation (Fig. 28-16), at high pressure (up to 60,000 psi) and has a jet typically 0.003in - 0.020in in diameter; AKA Waterjet machining or hydrodynamic machining
Term
Waterjet Machining (701)
Definition
uses a high- velocity fluid jet impinging on the workpiece to perform a slitting operation (Fig. 28-16), at high pressure (up to 60,000 psi) and has a jet typically 0.003in - 0.020in in diameter; AKA Waterjet cuttng or hydrodynamic machining
Term
Wire EDM (WEDM) (710)
Definition
involves the use of a thin, conductive wire as the tool that cuts thru the metal.
Term
Wire EDM (706)
Definition
AKA electrical discharge wire cutting; the electrode is a wire used for cutting through-cut features driving the workpiece on a CNC table; capable of producing complex 2-D patterns(Fig. 28-22) in hard to machine materials
Term
Wire Cutting -
Definition
...
Term
Islands –
Definition
isolated high spots that can be the result of improper agitation on large parts. They can also be formed due to inadequate cleaning or inhomogeneity with the work material.
Term
Laser beam machining, LBM –
Definition
has heat affected zone and recast layers that may require removal

Laser beam is focused on the WP and is transferred to thermal energy to perform operations (cutting, drilling, etc)
Term
Maskant –
Definition
etch resistant. Covers selected areas of the work piece in CHM.
Term
Nontraditional machining – NTM
Definition
have been developed since WWII to address the growing list of machining requirements which cannot be handled by conventional machining alone.
Term
Overcut
Definition
the distance between the surface of the electrode and the surface of the workpiece. Is constrained by the minimum interelectrode distance necessary for a spark. It depends on the gap voltage plus the chip size.
Term
Overhang
Definition
can result if the etchant is not properly agitated, particularly on deep cuts.
Term
Photochemical Machining
Definition
PCM – the use of photoresists in chemical machining. Limited to thin material. Tooling cost low. Used in microelectronics.
Term
Shaped-tube electrolytic machining
Definition
created in response to jet engine industry. Uses acidic electrolyte to minimize clogging while drilling shaped holes
Term
sinker EDM –
Definition
also known as ram EDM, or simply EDM, uses an electrode that is a die in the shape of the negative of the cavity to be produced in a bulk material. By feeding the die into the workpiece, the shape of the die is machined into the workpiece
Term
Spark erosion
Definition
process used in EDM by which a spark is generated in a thin interelectrode gap between a tool and a workpiece where a pulsating DC current is fed across the gap using a dielectric fluid. The dielectric fluid is ionized and a spark is created which vaporizes a tiny portion of the workpiece, leaving a void.
Term
Stepped machining
Definition
uses two iterations of the cut and peel method of applying a maskant to etch a stepped formation into a surface
Term
Stimulated emission-
Definition
when a second photon strikes the energized atom, the atom gives off 2 photons of identical wavelength moving in the same direction and with the same phase. p.712
Term
Thermal deburring or thermal energy method
Definition
developed for the removal of burrs and fins by exposing the workpiece to hot corrosive gases for a short period of time typically on the order of a few milliseconds p.715
Term
photochemical blanking –
Definition
through etching of the workpiece also called chemical blanking
Term
High definition plasma
Definition
also called precision PAC or fine plasma cutting. Uses a special nozzle, where either a high flow vortex or a magnetic field causes the plasma to spin rapidly and stabilizes the plasma pressure.
Term
Abrasive machining
Definition
is a material-removal process that involves the interaction of abrasive grits with the work piece at high cutting speeds and shallow penetration depth.
Term
Aluminum oxide
Definition
is the most widely used artificial abrasive. Also produced in an arc furnace from bauxite, iron filings, and small amounts of coke, it contains aluminum hydroxide, ferric oxide, silica, and other impurities.
Term
Attrition
Definition
refers to the abrasive wear action of the grits resulting in dulled edges, grit flattening, and wheel glazing.
Term
CBN (cubic boron nitride)
Definition
is not found in nature. It is produced by a combination of intensive heat and pressure in the presence of a catalyst. ______ is extremely hard, registering at 4700 on the Knoop scaled. It is the second hardest substance created by nature or manufactured and is often referred to, along with diamonds, as a superabrasive.
Term
Centerless grinding
Definition
makes it possible to grind both external and internal cylindrical surfaces without requiring the workpiece to be mounted between centers or in a chuck. This eliminates the requirement of center holes in some workpieces and the necessity for mounting the workpiece, thereby reducing the cycle time.
Term
coated abrasive
Definition
are being used increasingly in finishing both metal and nonmetal products. These are made by gluing onto a cloth or paperbacking.
Term
corundum
Definition
(Natural ) and diamonds are other nauturally occurring abrasive materials.
Term
Creep feed grinding
Definition
the work is fed very slowly past the wheel and the total downfeed or depth is accomplished in a single pass.
Term
Crush dressing
Definition
consists of forcing a hard roll having the same contour as the part to be ground against the grinding wheel while it is revolving; a water based coolant is used to flood the dressing zone. The crushing action fractures and dislodges some of the abrasive grains.
Term
Cylindrical grinding
Definition
is a type of grinding machine used for producing external cylindrical surfaces.
Term
Diamond
Definition
the hardest of all materials.
Term
Dressing
Definition
cleaning and sharpening the wheel. I f you do not ______, the wheel will not cut as well and will tend to plow and rub more.
Term
Emery
Definition
a mixture of alumina and magnetite is another natural abrasive still in use today and is used on coated paper and cloth.
Term
Friability
Definition
refers to the fracture of the grits and is the opposite of toughness.
Term
G ratio
Definition
(grinding ratio) the cubic inches of stock removed divided by the cubic inches of wheel lost (from lost of grains). It is a measure of grinding production and reflects the amount of work a wheel can do during its useful life.
Term
garnet
Definition
a diamond that is a natural, off-color stone that is not suitabe for gems
Term
grade
Definition
the bond strength which controls the fracturing of the grits. __________ is a measure of how strongly the grains are held in the wheel. It depends on the strength of the bonding materials and the amount of the bonding agent connecting the grains.
Term
grinding
Definition
process where the abrasives are bonded together into a wheel. It is the most common abrasive machining process. The performance of __________ wheels is greatly affected by the bonding material and the spatial arrangement of the particles grits.
Term
honing stones
Definition
similar to grinding but materials such as sulfur, resin or wax are added to the bonding agent to modify the cutting action.
Term
lapping
Definition
an abrasive surface-finishing process where fine abrasive particles are charged (or embedded) into a soft material (called a ___). The material can range from cloth to cat iron or copper.
Term
quartz
Definition
used primarily in coated abrasives and air blasting. It is a natural abrasive that has commercial importance
Term
resinoid bond
Definition
also called phenolic resins and cover a variety of work conditions; has replaced shellac and rubber wheels
Term
rubber bond
Definition
used to produce wheels that can operate at high speeds but must have a considerable degree of flexibility so as to resist side thrust. A rubber bond is composed of rubber, sulfur, and other vulcanizing agents that are mixed with the abrasive grains.
Term
shellac bond
Definition
wheels can be made this way by mixing the abrasive grains with shellac in a heated mixture, pressing or rolling into the desired shapes, and baking for several hours. This type of bond is used primarily for strong, thin wheels having some elasticity.
Term
silicate bond
Definition
this bond is formed with silicate of soda (waterglass) as the bond material. Because they are more brittle and not so strong as vitrified wheels, the abrasive grains are released more readily.
Term
silicon carbide
Definition
made by charging an electric furnace with silica sand, petroleum coke, salt, and sawdust. By passing large amounts of current through the charge, a temperature of over 4000 F is maintained for several hours, and a solid mass of silicon carbide crystals results.
Term
snagging
Definition
a type of rough manual grinding that is done to remove fins, gates, risers, and rough spots from castings or flash from forgings, preparatory to further machining.
Term
surface grinding
Definition
used primarily to grind flat surfaces, has a reciprocating table and horizontal spindle.
Term
truing
Definition
as grinding wheels lose their geometry during use, truing restores the original shape. A single-point diamond tool can be used to true the wheel while fracturing abrasive grains to expose new grains and new cutting edges on worn, glazed grains.
Term
vitrified bond
Definition
composed of clays and other ceramic substances. ____________ are proous, strong, rigid, and unaffected by oils, water, or temperature over the ranges usually encountered in metal cutting.
Term
Band-filling Machine- 652
Definition
This machine provides continuous cutting action. Most band filing is done on contour bandsawing machines by means of a special band file that is substituted for the usual bandsaw blade.
Term
Bandsaw- 648,650
Definition
These blades are available in straight, raker, wave, or combination sets. Blade width is very important in bandsawing because it determines the minimum radius that can be cut.
Term
Broach- 637
Definition
Used in production to finish holes, splines, and flat surfaces. Typical workpieces include small to medium sized castings, forgings, screw machine parts, and stampings. It is composed of a series of teeth, each tooth standing slightly higher then the last.
Term
Broaching- 637-640
Definition
It is widely used and particularly well suited for mass production. Broaching usually produces better accuracy and finish than can be obtained by drilling, boring, or reaming.
Term
Burnishing teeth- 642
Definition
On some round broaches, ___________ are provided for finishing. These have no cutting edges but are rounded disks that are from 0.001 to 0.003 inches larger than the size of the hole. The resulting rubbing action smooths and sizes the hole.
Term
Circular saw- 645, 647
Definition
These saws necessarily differ somewhat from straight blade forms. Because they must be relatively larger in comparison with the work, only the sizes up to about 19 inches in diameter have teeth that are cut into the disk.
Term
Cold saw- 645, 647
Definition
This is another name for a circular saw that is used for cutting metal. These saws rapidly cut and produce chips like a milling cutter while producing surfaces that are comparable in smoothness and accuracy with surfaces made by slitting saws in a milling machine or by a cutoff tool in a lathe.
Term
Filing (Pg 651)
Definition
Metal-removing action is the same as in sawing in that chips are removed by cutting teeth that are arranged in succession along same plane on the surface of a tool
Term
Hacksaw (Pg 645)
Definition
one of 3 basic configurations of saw blades, the blade is tough and thin. It is also disposable
Term
Planing (Pg 632-635)
Definition
Among the oldest single-point machining processes, work is moved past one or more stationary single-point cutting tools and can be used to produced horizontal, vertical, or inclined flat surfaces on large workpieces (too large for shapers), as well as for producing long flat cuts like those in the way of machine tools
Term
Pull broach (Pg 637-639)
Definition
the pull end of the broach is passed through the part and key mates to the slot
Term
Push broach (Pg 639)
Definition
Push broaching machines are similar to an arbor press with a guided ram; typical capacities are 5 to 50 tons. This must be strong enough so that it will not buckle. If the length-to-diameter ratio L/Dr is greater than 25, the broach must be considered a long column which can buckle if overloaded.
Term
Reciprocating Saw- p648
Definition
One of the 3 classifications of metal-sawing maching. There are two types, a manual hacksaw and a power hacksaw. These machines consist of a bed, a workholding frame and a power or manual mechanism for reciprocating.
Term
Rise per tooth- p638
Definition
the feed per tooth in broaching id the change in hieght of successive teeeth. This is called______________. The sum of this gives the depth of cut. It also determines the chip load and varies depending on the type of broaching
Term
Sawing- p645
Definition
is a basic machining proccess in which chips are produced by a succession of small cutting edges, or teeth, arranged in a narrow line on a "blade"
Term
Shaping- p632
Definition
has largely been replaced by milling and broching as a production process. In this the workpiece is fed at right angles to the cutting motion between successive strokes of the tool.
Term
Surface Broach- p641,43
Definition
in this, the the rise per tooth is typically .003in to .006in. Smaller ones are made of solid construction but larger ones are made of modular construction
Term
Tooth-set- p646
Definition
refers to the manner in which teeth are offset from the centerline in order to make the kerf wider than the gage(thickness of the back) of the blade
Term
Workholders
Definition
hold and locate the work in the machine tool with respect to the cutting tool
Term
clamping
Definition
holding or maintaining the part in that location during cutting operations (resisting cutting forces)
Term
Location
Definition
determine the position or location of geometrc shapes with respect to each other
Term
jig
Definition
special workholding device that determines location dimensions that are produced by machining or fastening operations
Term
fixture
Definition
workholding device that holds work during mahining or assembly operations and establishes size dimensions. IT IS DESIGNED AND CONSTRUCTED FOR A PARTICULAR PART OR SHAPE
Term
3-2-1 Principle
Definition
for a positive location, the fixture must position the workpiece in each of three perpendicular planes
Term
Channel Jigs
Definition
derive their name from the cross-sectional shape of the main member. Can only be used with parts having fairly simple shape
Term
Ring Jigs
Definition
used only for drilling round parts.
Term
leaf jigs
Definition
derive their name from the hinged leaf or cover that can be swung open to permit the workpiece to be inserted and then closed to clamp the work in position
Term
box jigs
Definition
derive their name from their boxlike construction. Have fixed sides and a hinged cover or leaf which opens to permit loading the workpiece, and a cam that locks the workpiece in place
Term
intermediate jig concept
Definition
the workholding devices are designed so that they all appear the same to the tool but different to the parts. The jigs or fixtures are all different, but the plates identical.
Term
strap clamp
Definition
comes in many forms, force can be applied by a hand knob, a cam, or a wrench turning down a nut
Term
toggle clamp
Definition
accomodates only small thickness variation from part to part, yet proivides consistent clamping force
Term
assembly jig
Definition
of the open-frame type, provide for the introduction of several component parts and the use of some type of fastening equipment
Term
magnetic chucks
Definition
used for ferromagnetic materials, available in rectangular shapes
Term
vacuum chucks
Definition
the holes of the work plate are connected to a vacuum pump, and can be opened or closed by means of valve screws
Term
Acetlyne
Definition
C2H2, used along with oxygen to produce monoxide and hydrogen (in the first stage)
Term
Carburizing Flame
Definition
Excess fuel produces this. This type of flame is used when welding in Monel and high carbon steels
Term
Filler Metal
Definition
added in the form of solid metal wire or rod to fill slight gaps
Term
flame straightening
Definition
the use of controlled, localized upsetting as a means of straightening warped or buckled plates
Term
flux
Definition
used to clean the surfaces and remove contaminating oxide
Term
fusion welding
Definition
Almost all oxyfuel gas welding is of this type. The metals to be joined are simply melted where a weld is desired
Term
kerf
Definition
a gap
Term
MAPP
Definition
an alternative fuel gass, methyl acetylene propadiene
Term
neutral flame
Definition
ratio of 1:1 to 1.15:1, most welding is done with this type of flame because it has the LEAST chemical effect on the heated metal
Term
oxidizing flame
Definition
ratio of 1.5:1, hotter than a neutral flame. Used when welding copper and copper alloys, but considered harmful when welding steel
Term
oxyfuel gas cutting
Definition
AKA flame cutting, metal is melted by the flame of the oxygas fuel
Term
oxyfuel gas welding
Definition
a group of welding processes that use the flame produced by the combustion of a fuel gas and oxygen as their heat source
Term
oxygen lance cutting
Definition
used if the workpiece is already hot from another process. No heating is required. A supply of oxygen thru a small pipe is used initiate and continue a cut
Term
thermal cutting
Definition
a cutting process (?)
Term
torch
Definition
used to burn acetylene and oxygen
Term
arc
Definition
between 2 electrodes, a concentrated heat source tht can approach high teperatures
Term
arc welding
Definition
All ______________ processes employ the same basic circuit. Welding currents vary from 1 to 4000 amps (100-1000 is the most typical)
Term
bulk welding
Definition
modification of the submerged arc process, iron powder is deposited in the joint as a means of increasing deposition rate
Term
consumable electrode process
Definition
part of the the group of arc welding process where the electrode is consumed and thus supplies the metal needed to fill the joint
Term
DCEN
Definition
when direct current is used and the elctrode is made negative, direct-current electrode-negative. characterized by fast melting of the electrode and a shallow molten pool on the workpiece
Term
DCEP
Definition
if the workpiece is made negative and the electrode positive, direct-current electrode-positive
Term
electrode
Definition
terminal thru which electric current passes
Term
flux
Definition
used to deoxidize and remove impurities from molten metal
Term
flux-cored arc welding
Definition
overcomes shielded metal arc limitations by moving powdered flux to the interior of a continuous tubular electrode
Term
gas metal arc welding
Definition
If the shielding gas flowing through the torch becomes the primary protection for the arc and molten metal, the electrode becomes a continuous uncoated metal wire.
Term
gas tungsten arc welding
Definition
a nonconsumable tungsten electrode provides the arc but not the filler metal. The pointed electrode is positioned, and inert gas flows to provide a protective shield around the electrode.
Term
globular transfer
Definition
If voltage and aperage are increased, the mode becomes __________. The electrode melts from the heat of the arc and the metal drops form with a diameter equal to the electrode wire
Term
kerf
Definition
slit or notch
Term
nonconsumable electrode process
Definition
employs a tungsten electrode which is not consumed by the arc, except by relatively slow variation. A separate metal wire is required to supply the filler metal
Term
orifice gas
Definition
gas that transfers it heat to the workpiece and melts the metal
Term
penetration
Definition
the depth of melting in the workpiece
Term
plasma
Definition
When an inert gas is forced through a constricted arc and heated ______ is formed
Term
plasma arc welding
Definition
the arc is maintained between either the welding gun or the workpiece
Term
power supply
Definition
available in DC or AC, employ the drooping voltage characteristics
Term
residual stresses
Definition
Produced from all thermal cutting processes where the cut surface is generalliy in tension
Term
reverse polarity
Definition
leads from a direct current power source whereby the electrode is the positive pole and the work piece is the negative pole of the arc.
Term
shielded metal arc welding
Definition
AKA stick welding, most common arc welding process. Low cost, and very versatile. However, it pis discontinuous, and requires slag removal after each welding pass.
Term
short circuit transfer
Definition
The lowest currents and the use of CO2 shield gas promotes ________________.
Term
slag
Definition
a protective coating used to accumulate impurities, prevent oxidation, and slow cooling of the weld
Term
spot weld
Definition
an inert-gas tungsten arc gun joins the two pieces
Term
spray transfer
Definition
happens with higher currents and voltages, along with argon gas shielding and DCEP conditions. Small droplets emerge from a pointed electrode at a fast rate
Term
straight polarity
Definition
ads from a direct current power source whereby the work piece is the positive pole and the electrode is the negative pole of the arc.
Term
stud welding
Definition
an arc welding process used to attach studs, screws, pins, or other fasteners to a metal surface
Term
submerged arc welding
Definition
No shielding gas is used. A thick later of granular flux is deposited ahead of the electrode. Only a few small flames are visible
Term
transferred arc
Definition
An arc established between the plasma torch and the workpiece.
Term
variable polarity
Definition
power supplies that alternate between DCEN and DCEP, but use regular waveforms to vary the fraction of time in each mode
Term
assist gas
Definition
used to blow molten metal through the cut, cool the workpiece, and assist in the combustion of the material
Term
autogeneous weld
Definition
simple fusion welds without filler metal
Term
butt welding
Definition
has its greatest use in the manufacture of pipes and tubes
Term
cold welding
Definition
variation of forge welding that uses no heat but produces metallurgical bonds by a means of cold plastic deformation
Term
diffusion bonding
Definition
occurs when properly prepared surfaces are maintained in contact under sufficient pressure and time at an elevated temperature
Term
electron-beam welding
Definition
fusion welding process where heating results from the impingement of a beam of high-velocity electrons on the metal to be welded
Term
electroslag welding
Definition
effective process for welding thick sections of steel plate. No arc. Heat is derived from the passage of electrical current through a liquid slag
Term
explosive welding
Definition
used to bond corrosion resistance sheets to heavier plates of base metal. An explosive material is placed on top of both metals and detonated in a progressive fashion
Term
faying surfaces
Definition
resistance between the surfaces to be joined
Term
flash
Definition
oxides and other surface impurities are dispaced into this, can be removed by subsequent machining
Term
flash welding
Definition
2 pieces of metal are first secured in current-carrying grips and lightly touched together. An intense flashing arc is created across the gap, abd the pieces are forced together under high pressure
Term
forge welding
Definition
most ancient of the welding processes. Uses a charcoal forge and hammer
Term
forge-seam welding
Definition
heated strip of steel is formed into a cylinder, the edges are pressed together in either a lap, or butt configuration
Term
friction welding
Definition
where the heat required to produce the joint is generated by friction heating at the interface. The components to be joined are prepared to have smooth, square-cut surfaces
Term
friction stir welding
Definition
frictional heat is generated by a nonconsumable probe that is rotated at high speed between the abutting edges of rigidly clamped plates. A plasticized region is continually created
Term
hardfacing
Definition
used to obtain improved resistance to wear
Term
hot-gas welding
Definition
a gas is heated by an electric coil as it passes through a welding gun . Hot gas steam emerges and impinges on the joint area. Usually a slow process
Term
hot-plate welding
Definition
uses an external heat source. The parts are are held in fixtures and pressed against the opposite sides of an electrically heated tool. Simplest mass production technique to join plastics
Term
implant welding
Definition
metal inserts are placed between the plastics to be joined and heated by means of induction. Thermoplastic material melts around the inserts and forms a joint
Term
inertia welding
Definition
a modification of friction welding where the moving piece is attached to a flywheel, the flywheel is brought to a speed and the kinetic energy is turned to friction, which joins the pieces
Term
infrared radiation
Definition
process to weld thermoplastics
Term
kerf
Definition
groove or slit in the material caused by cutting
Term
lap joint
Definition
A welded joint in which two overlapping metal parts are joined by means of a fillet, plug or slot weld.
Term
laser-beam cutting
Definition
begins by drilling a hole through the material and then moving the beam in a programmed path. The heat from the beam is used to melt or evaporate the material being cut
Term
laser-beam welding
Definition
beam can be focused to a small diameter and high power. Used to melt material at the joint
Term
lase spot welding
Definition
a noncontact process, no electrodes are involved. Performed with access to only one side of the joint
Term
metallizing
Definition
if a non transferred arc is used and only a mechanical bond is produced
Term
microwave heating
Definition
process to weld thermoplastics
Term
molding plates
Definition
water-cooled means of confining molten metal to the gap
Term
nugget
Definition
coalesced metal formed between faying surfaces
Term
percussion welding
Definition
a rapid discharge of stored energy produces a brief period of arcing which is followed by the rapid application of force to expel the molten metal and produce the joint
Term
projection welding
Definition
used if increased strength is required and multiple welds are needed. Where a dimple is embossed and flattened by the current
Term
resistance welding
Definition
where both heat and pressure are used to induce coalescence. Electrodes are placed in contact with the material and electrical resistance heating is used to raise the temp of the workpiece and the interface between them
Term
resistance spot welding
Definition
most widely used form of resistance welding. Fast, economic way to join overlapped materials that do not require disassembly
Term
rocker arm machine
Definition
used for light production work where cycles are not required. Lower electrode arm is stationary while the upper electrode (mounted on a pivot arm) is brought into contact by means of a foot pedal
Term
roll bonding
Definition
two or more sheets or plates of metal are passed through a rolling mill and joined together
Term
surfacing
Definition
AKA overlaying, process of depositing a layer of weld material on the surface or edge of a base material of different composition.
Term
thermit
Definition
refers to a mechanical mixture of aluminum and iron oxide. When ignited, it reacts chemically
Term
thermit welding
Definition
superheated molten metal and slag are produced from an exothermic chemical reaction between a metal oxide and a metallic reducing agent.
Term
thermoplastic polymer
Definition
materials that can be welded because the material can be melted without degradation
Term
thermosetting polymer
Definition
materials that do not soften with heat. They tend to only char or bur and must be joined with fasteners or adhesives
Term
transgun
Definition
small integral transformer gunts that offer reduced power losses and process efficiency
Term
ultrasonic welding
Definition
a solid state process where coalescence is produced by the localized application od high-frequency vibrations to surfaces tht are held together under light, normal pressure
Term
upset welding
Definition
similar to flash welding, but the heat is achieved through electrical resistance. The parts are clamped to the machine, pressure is applied, and current is passed through the joint
Term
vibration welding
Definition
relative movement between the two parts is used to generate heat in the direction parallel to the interface
Term
braze welding
Definition
molten filler is deposited by gravity, capillary action is not requred to distribute the filler metal
Term
brazing
Definition
the permanent joining of similar or dissimilar metals or ceramics through the ue of heat and a filler metal whose melting temperature is below the melting point of the materials being joined
Term
butt joint
Definition
does not requre additional thickness in the vicinity of the join. Most often used where strength requirements are not critical
Term
capillary action
Definition
used to distribute the filler material between the closely fiitting surfaces of the joint
Term
dip brazing
Definition
assemblies are immersed in a bath of molten brazing metal. Bath provides both the heat and metal for the joint
Term
fluidity
Definition
a measure of the flow characteristics of the molten braze metal and is a function of the metal, its remp, and clearance
Term
furnace brazing
Definition
when flux and filler material are preloaded into the joints and simultaneously heated
Term
joint clearance
Definition
contributing factor to joint strength. If its too tight, may have unfilled voids. If its too lose, filler might escape
Term
lap joint
Definition
provide bonding areas considerable larger than butt. Use when maximum strength is desired
Term
leadfree solder
Definition
solder metal without lead (lead is banned from solder in the USA)
Term
silver solder
Definition
alloys based on silver and copper with brazing temperatures significantly below pure copper
Term
soldering
Definition
a brazing type of operation where the filler metal has a melting temperature. Typically used for connecting thin metals
Term
torch brazing
Definition
common type of brazing where the gas flame torch is used. Most brazing is done in this manner
Term
wettability
Definition
a strong function of the surface tensions between the braze metal and the base alloy. Good when surfaces are clean
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