CH 27 (Heat Treatment of Metals), Metal casting processes, CH 8 Multiple Choice Q's, Fundamentals of metal casting, Chapter 18, CH 15 Multiple Choice Q's, CH 18: Fundamentals of Metal Forming, Chapter 16: Powder Metallurgy
a,c
10.11 Two important relationships that determine the flow of molten metal in casting are which of the following (two correct answers): (a) Bernoulli's theorem, (b) Chvorinov's rule, (c) continuity law, (d) flow curve, (e) Hooke's law, or (f) Ohm's law?
a
10.12 Total solidification time is defined as which one of the following: (a) time between pouring and complete solidification, (b) time between pouring and cooling to room temperature, (c) time between solidification and cooling to room temperature, or (d) time to give up the heat of fusion?
a
10.4 The upper half of a sand-casting mold is called which one of the following: (a) cope, (b) drag, (c) flask, or (d) pattern?
b
10.5 In casting, a flask is which one of the following: (a) beverage bottle for workers who perform casting, (b) box which holds the cope and drag, (c) container for holding liquid metal, or (d) metal which extrudes between the mold halves?
a
10.6 The pattern that determines the geometry of the casting in expendable mold processes is usually made (a) oversized, (b) the same size, or (c) undersized relative to the dimensions of the casting?
a
11.2 In sand casting, the volumetric size of the pattern is (a) bigger than, (b) same size as, or (c) smaller than the cast part?
b
11.20 Cupolas are furnaces used to melt which of the following metals (one best answer): (a) aluminum, (b) cast iron, (c) steel, or (d) zinc?
c
11.21 A misrun is which one of the following defects in casting: (a) globules of metal becoming entrapped in the casting, (b) metal is not properly poured into the downsprue, (c) metal solidifies before filling the cavity, (d) microporosity, and (e) "pipe" formation?
c
11.22 An irregularity in the surface of the casting caused by erosion of the sand during pouring is called which one of the following sand casting defects: (a) penetration, (b) sand blow, (c) sand wash, or (d) scabs?
c
11.23 Which one of the following casting metals is most important commercially: (a) aluminum and its alloys, (b) bronze, (c) cast iron, (d) cast steel, or (e) zinc alloys?
c
11.3 Silica sand has which one of the following compositions: (a) Al2O3, (b) SiO, (c) SiO2, or (d) SiSO4?
b
11.7 Shell molding is best described by which one of the following: (a) casting operation in which the molten metal has been poured out after a thin shell has been solidified in the mold, (b) casting process in which the mold is a thin shell of sand bonded by a thermosetting resin, (c) sand-casting operation in which the pattern is a shell rather than a solid form, or (d) casting operation used to make artificial sea shells?
a
11.8 The expanded polystyrene casting process uses a mold of sand packed around a polystyrene foam pattern that vaporizes when the molten metal is poured into the mold: (a) true or (b) false?
e
11.9 Investment casting is also known by which one of the following names: (a) fast-payback molding, (b) full-mold process, (c) lost-foam process, (d) lost-pattern process, or (e) lost-wax process?
The expanded polystyrene casting process uses a mold of sand packed around a polystyrene foam pattern that vaporizes when the molten metal is poured into the mold: (a) true or (b) false?
True
(c) carburizing
Which one of the following surface-hardening treatments is the most common: (a) boronizing, (b) carbonitriding, (c) carburizing, (d) chromizing, or (e) nitriding?
MC 16.9 Which of the following processes combines pressing and sintering of the metal powders? (3) a) hot isostatic pressing b) hot pressing c) metal injection molding d) pressing and sintering e) spark sintering
a, b, e
MC 16.5 Which of the following statements is correct in the context of metallic powders? (3) a) porosity+packing factor=1 b) packing factor=1/porosity c) packing factor=1-porosity d) packing factor=-porosity e) packing factor=(bulk density)/(true density)
a, c, e
Which of the following metals would typically be used in die casting: (a) aluminum, (b) cast iron, (c) steel, (d) tin, (e) tungsten, and (f) zinc?
aluminum, tin, zinc
MC 16.22 Which of the following most closely typifies the sintering temperatures in PM? a) 0.5 Tm b) 0.8 Tm c) Tm (Tm=melting temp of material)
b
MC 16.2 For a given weight of metallic powders the total surface area of the powder is increased by which of the following? (2) a) larger particle size b) smaller particle size c) higher shape factor d) smaller shape factor
b and c
MC 16.7 Impregnation refers to which of the following? (2) a) filling the pores of the PM part with a molten metal b) putting polymers into the pores of a PM part c) soaking oil by capillary action into the pores of a PM part d) something that should not happen in a factory
b, c
MC 16.1 The particle size that can pass through a screen is obtained by taking the reciprocal of the mesh count of the screen. a) true b) false
b. The given description neglects consideration of the screen wire thickness
15.13 Which of the following are alternative names for indirect extrusion: (a) backward extrusion, (b) direct extrusion, (c) forward extrusion, (d) impact extrusion, and (e) reverse extrusion?
backward extrusion, reverse extrusion
Which of the following are alternative names for indirect extrusion (two correct answers)
backward extrusion, reverse extrusion
15.5 The maximum possible draft in a rolling operation depends on which of the following parameters: (a) coefficient of friction between roll and work, (b) roll diameter, (c) roll velocity, (d) stock thickness, (e) strain, and (f) strength coefficient of the work metal?
coefficient of friction between roll and work, roll diameter
The maximum possible draft in a rolling operation depends on which of the following parameters (two correct answers)
coefficient of friction between roll and work, roll diameter
15.10 Which of the following operations are closely related to open-die forging: (a) cogging, (b) flashless forging, (c) fullering, (d) impression-die forging, (e) Mannesmann process, (f) precision forging, and (g) upsetting?
cogging, fullering, upsetting
Which of the following operations are closely related to open-die forging (three best answers)
cogging, fullering, upsetting
Which of the following are classified as forging operations (four correct answers)
coining, fullering, swagging, upsetting
15.12 Which of the following are classified as forging operations: (a) coining, (b) fullering, (c) impact extrusion, (d) roll piercing, (e) swaging, (f) thread rolling, (g) trimming, and (h) upsetting?
coining, fullering, upsetting, swaging
MC 16.4 Which of the following powder shapes would have the lowest inter-particle friction? a) acicular b) cubic c) flaky d) spherical e) rounded
d
Johnson's formula is associated with which one of the four bulk deformation processes
extrusion
15.8 Production of pipes and tubes is associated with which of the following bulk deformation processes: (a) extrusion, (b) hobbing, (c) ring rolling, (d) roll forging, (e) roll piercing, (f) tube sinking, and (g) upsetting?
extrusion, roll piercing, tube sinking
Production of pipes and tubes is associated with which of the following bulk deformation processes (three correct answers)
extrusion, roll piercing, tube sinking
Flash in impression die forging serves no useful purpose and is undesirable because it must be trimmed from the part after forming
false
The production of tubing is possible in indirect extrusion but not in direct extrusion
false
15.9 Which of the following stress or strength parameters is used in the computation of the maximum force in a forging operation: (a) average flow stress, (b) compression strength, (c) final flow stress, (d) tensile strength, or (e) yield strength?
final flow stress
Which of the following stress or strength parameters is used in the computation of the maximum force in a forging operation
final flow stress
Which of the following are advantages of die casting over sand casting (four best answers): (a) better surface finish, (b) closer tolerances, (c) higher melting temperature metals can be cast, (d) higher production rates, (e) larger parts can be cast, and (f) mold can be reused?
higher production rates, closer tolerances, better surface finish, mold can be reused
Which of the following casting processes are expendable mold operations: (a) centrifugal casting, (b) die casting, (c) investment casting, (d) low pressure casting, (e) sand casting, (f) shell molding, (g) slush casting, and (h) vacuum molding?
investment casting, sand casting, shell molding, vacuum molding
A misrun is which one of the following defects in casting: (a) globules of metal becoming entrapped in the casting, (b) metal is not properly poured into the downsprue, (c) metal solidifies before filling the cavity, (d) microporosity, and (e) "pipe" formation?
metal solidifies before filling the cavity
15.18 Theoretically, the maximum reduction possible in a wire drawing operation, under the assumptions of a perfectly plastic metal, no friction, and no redundant work, is which one of the following: (a) zero, (b) 0.63, (c) 1.0, or (d) 2.72?
0.63
Powder Metallurgy- Outline
1. The Characterization of Engineering Powders 2. Production of Metallic Powders 3. Conventional Pressing and Sintering 4. Alternative Pressing and Sintering Techniques 5. Materials and Products for PM 6. Design Considerations in Powder Metallurgy
a
10.1 Casting is a process in which molten metal flows into a mold where it solidifies in the shape of the mold cavity; the term casting also applies to the part that is made by this process: (a) true or (b) false?
c,d
10.10 Turbulence during pouring of the molten metal is undesirable for which of the following reasons (two best answers): (a) it causes discoloration of the mold surfaces, (b) it dissolves the binder used to hold together the sand mold, (c) it increases erosion of the mold surfaces, (d) it increases the formation of metallic oxides that can become entrapped during solidification, (e) it increases the mold filling time, and (f) it increases total solidification time?
a
10.8 The internal surfaces of a casting are determined during the casting process by means of which one of the following: (a) core, (b) gating system, (c) parting line, (d) pattern, or (e) sprue?
e
10.9 Heating a metal from room temperature to pouring temperature in a casting operation depends on all of the following properties except which one: (a) density, (b) heat of fusion, (c) melting temperature, (d) specific heat, or (e) thermal expansion?
d
11.1 Which one of the following casting processes is the most widely used: (a) centrifugal casting, (b) die casting, (c) investment casting, (d) sand casting, or (e) shell casting
b
11.10 In plaster mold casting, the mold is made of which one of the following materials: (a) Al2O3, (b) CaSO4-H2O, (c) SiC, or (d) SiO2?
a
11.11 The Antioch process is similar to plaster-mold casting but uses a mixture of sand and plaster to make the mold: (a) true or (b) false?
a,b,d,f
11.17 Which of the following are advantages of die casting over sand casting (four best answers): (a) better surface finish, (b) closer tolerances, (c) higher melting temperature metals can be cast, (d) higher production rates, (e) larger parts can be cast, and (f) mold can be reused?
b,d
11.18 Which of the following names are applied to a process in which a molten metal is poured into a heated lower die, and the upper die is closed to create the mold cavity only after solidification begins (two correct answers): (a) liquid-metal casting, (b) liquid-metal forging, (c) rheocasting, (d) squeeze casting, or (e) thixocasting?
c
11.19 Which one of the following is the name of the casting process in which molten metal is poured into a rotating mold to produce a tubular part: (a) centrifuge casting, (b) semicentrifugal casting, or (c) true centrifugal casting?
b
11.4 For which one of the following reasons is a green mold named: (a) green is the color of the mold, (b) moisture is contained in the mold, (c) the mold is cured, or (d) the mold is dry?
d
11.5 Given that Wm = weight of the molten metal displaced by a core and Wc = weight of the core, the buoyancy force is which one of the following: (a) downward force = Wm + Wc, (b) downward force = Wm - Wc, (c) upward force = Wm + Wc, or (d) upward force = Wm - Wc?
c,e,f,h
11.6 Which of the following casting processes are expendable mold operations (four correct answers): (a) centrifugal casting, (b) die casting, (c) investment casting, (d) low pressure casting, (e) sand casting, (f) shell molding, (g) slush casting, and (h) vacuum molding?
Which of the following are metals commonly cast in permanent mold casting (three best answers): (a) aluminum, (b) brass, (c) gold, (d) magnesium, (e) nickel, (f) steel, and (g) tungsten?
Aluminium, magnesium, brass (copper-based alloy) EXTRA -> cast iron
Which of the following are advantages and characteristics of hot working relative to cold working (four correct answers): (a) fracture of workpart is less likely, (b) friction is reduced, (c) increased strength properties, (d) isotropic mechanical properties, (e) less overall energy is required, (f) lower deformation forces is required, (g) more significant shape changes are possible, and (h) strain-rate sensitivity is reduced?
Answer. (a), (d), (f), and (g).
The coefficient of friction between the part and the tool in cold working tends to be (a) higher, (b) lower, or (c) no different relative to its value in hot working?
Answer. (b).
The flow curve expresses the behavior of a metal in which of the following regions of the stress-strain curve: (a) elastic region or (b) plastic region?
Answer. (b).
Which of the following is typical of the starting work geometry in sheet metal processes: (a) high volume-to-area ratio or (b) low volume-to-area ratio?
Answer. (b).
Which of the following are bulk deformation processes (three correct answers): (a) bending, (b) deep drawing, (c) extrusion, (d) forging, (e) rolling, and (f) shearing?
Answer. (c), (d), and (e).
Increasing strain rate tends to have which one of the following effects on flow stress during hot forming of metal: (a) decreases flow stress, (b) has no effect, or (c) increases flow stress?
Answer. (c).
Hot working of metals refers to which one of the following temperature regions relative to the melting point of the given metal on an absolute temperature scale: (a) room temperature, (b) 0.2Tm, (c) 0.4Tm, or (d) 0.6Tm?
Answer. (d).
The average flow stress is the flow stress multiplied by which of the following factors: (a) n, (b) (1+n), (c) 1/n, or (d) 1/(1+n), where n is the strain-hardening exponent?
Answer. (d).
In sand casting, the volumetric size of the pattern is (a) bigger than, (b) same size as, or (c) smaller than the cast part?
Bigger than
In plaster mold casting, the mold is made of which one of the following materials: (a) Al2O3, (b) CaSO4-H2O, (c) SiC, or (d) SiO2?
CaSO_4-H_2O
Cupolas are furnaces used to melt which of the following metals: (a) aluminum, (b) cast iron, (c) steel, or (d) zinc?
Cast iron
Shell molding is best described by which one of the following: (a) casting operation in which the molten metal has been poured out after a thin shell has been solidified in the mold, (b) casting process in which the mold is a thin shell of sand bonded by a thermosetting resin, (c) sand-casting operation in which the pattern is a shell rather than a solid form, or (d) casting operation used to make artificial sea shells?
Casting process in which the mold is a thin shell of sand bonded by a thermosetting resin.
15.20 Johnson's formula is associated with which one of the four bulk deformation processes: (a) bar and wire drawing, (b) extrusion, (c) forging, and (d) rolling?
Extrusion
15.11 Flash in impression die forging serves no useful purpose and is undesirable because it must be trimmed from the part after forming: (a) true or (b) false?
False The flash has friction against the die gap surface which helps contain the metal in the die cavity.
15.14Production of tubing is possible in indirect extrusion but not in direct extrusion: (a) true or (b) false?
False tubing is possible for both
(a) aging
In precipitation hardening, the hardening and strengthening of the metal occurs in which one of the following steps: (a) aging, (b) quenching, or (c) solution treatment?
Which of the following qualifies as a precision-casting process: (a) ingot casting, (b) investment casting, (c) plaster-mold casting, (d) sand casting, and (e) shell molding?
Investment casting, plaster-mold casting
Powder Metallurgy (PM)
Metal processing technology in which parts are produced from metallic powders Usual PM production sequence: 1. Pressing - powders are compressed into desired shape to produce *green compact ~ Accomplished in press using punch-and-die 2. Sintering - green compacts are heated to bond the particles into a hard, rigid mass ~ Temperatures are below melting point
(b) brine
Of the following quenching media, which one produces the most rapid cooling rate: (a) air, (b) brine, (c) oil, or (d) pure water?
(d) steel
On which one of the following metals is the treatment called austenitizing be performed: (a) aluminum alloys, (b) brass, (c) copper alloys, or (d) steel?
Which one of the following casting processes is the most widely used: (a) centrifugal casting, (b) die casting, (c) investment casting, (d) sand casting, or (e) shell casting?
Sand casting
Silica sand has which one of the following compositions: (a) Al2O3, (b) SiO, (c) SiO_2, or (d) SiSO_4?
SiO_2
15.3 The starting workpiece in hot rolling of steel plate and sheet stock is which one of the following: (a) bar stock, (b) billet, (c) bloom, (d) slab, or (e) wire stock?
Slab
Which of the following casting processes are permanent mold operations: (a) centrifugal casting, (b) expanded polystyrene process, (c) sand casting, (d) shell molding, (e) slush casting, and (f) vacuum molding.
Slush casting, die casting, centrifugal casting
(c) hardenability
The Jominy end-quench test is designed to indicate which one of the following: (a) cooling rate, (b) ductility, (c) hardenability, (d) hardness, or (e) strength?
(f) tempering
The treatment in which the brittleness of martensite is reduced is called which one of the following: (a) aging, (b) annealing, (c) austenitizing, (d) normalizing, (e) quenching, or (f) tempering?
15.2 Rolling is a bulk deformation process in which the thickness of the work is reduced by compressive forces exerted by two opposing rolls: (a) true or (b) false?
True
(b) electron beam heating (d) induction heating (e) laser beam heating
Which of the following are selective surface-hardening methods (three correct answers): (a) austenitizing, (b) electron beam heating, (c) fluidized bed furnaces, (d) induction heating, (e) laser beam heating, and (f) vacuum furnaces?
(a) increase hardness (d) reduce brittleness (f) relieve stresses
Which of the following are the usual objectives of heat treatment (three best answers): (a) increase hardness, (b) increase melting temperature, (c) increase recrystallization temperature, (d) reduce brittleness, (e) reduce density, and (f) relieve stresses?
MC 16.3 As particle size increases, inter-particle friction a) increases b) decreases c) stays the same
a
MC 16.6 Repressing refers to a pressworking operation used to compress a sintered part in a closed die to achieve closer sizing and better surface finish a) true b) false
a
MC 16.8 In cold isostatic pressing the mold is most typically made of which of the following? a) rubber b) sheet metal c) textile d) thermosetting polymer e) tool steel
a
MC 16.10 Which of the following design features would be difficult or impossible to achieve by conventional pressing and sintering? (3) a) outside rounded corners b) side holes c) threaded holes d) vertical-stepped holes e) vertical wall thickness of 1/8 in
a, b, c
15.16 Which of the following stress or strength parameters is used in the computation of the force in an extrusion operation (one best answer): (a) average flow stress, (b) compression strength, (c) final flow stress, (d) tensile strength, or (e) yield strength?
average flow stress
15.6 Which of the following stress or strength parameters is used in the computation of rolling force: (a) average flow stress, (b) compression strength, (c) final flow stress, (d) tensile strength, or (e) yield strength?
average flow stress
Which of the following stress or strength parameters is used in the computation of rolling force
average flow stress
Which of the following stress or strength parameters is used in the computation of the force in an extrusion operation
average flow stress
15.19 Which of the following bulk deformation processes are involved in the production of nails for lumber construction: (a) bar and wire drawing, (b) extrusion, (c) flashless forging, (d) impression die forging, (e) rolling, and (f) upsetting?
bar and wire drawing, flashless forging, impression die forging
15.1 Which of the following are basic bulk deformation processes in metal forming: (a) bar drawing, (b) blanking, (c) deep drawing, (d) extrusion, (e) forging, and (f) stamping?
bar drawing, extrusion, forging
Which one of the following casting metals is most important commercially: (a) aluminum and its alloys, (b) bronze, (c) cast iron, (d) cast steel, or (e) zinc alloys?
cast iron
15.7 Which of the following rolling mill types are associated with relatively small diameter rolls in contact with the work: (a) cluster mill, (b) continuous rolling mill, (c) four-high mill, (d) reversing mill, and (e) three-high configuration?
cluster mill, four-high mill
15.17 In which of the following extrusion operations is friction a factor in determining the extrusion force: (a) direct extrusion or (b) indirect extrusion?
direct extrusion
In which of the following extrusion operations is friction a factor in determining the extrusion force
direct extrusion
Investment casting is also known by which one of the following names: (a) fast-payback molding, (b) full-mold process, (c) lost-foam process, (d) lost-pattern process, or (e) lost-wax process?
lost-wax process
Which of the following names are applied to a process in which a molten metal is poured into a heated lower die, and the upper die is closed to create the mold cavity only after solidification begins: (a) liquid-metal casting, (b) liquid-metal forging, (c) rheocasting, (d) squeeze casting, or (e) thixocasting?
squeeze casting, liquid-metal forging
d
10.13 During solidification of an alloy when a mixture of solid and liquid metals is present, the solid liquid mixture is referred to as which one of the following: (a) eutectic composition, (b) ingot segregation, (c) liquidus, (d) mushy zone, or (e) solidus?
b
10.14 The empirical relationship that determines total solidification time in casting is known as which one of the following: (a) Bernoulli's theorem, (b) Chvorinov's rule, (c) continuity law, (d) flow curve, (e) Hooke's law, or (f) Ohm's law?
f
10.15 According to the empirical relationship in the previous question, total solidification time is proportional to which one of the following quantities: (a) (A/V)n, (b) Hf, (c) Tm, (d) V, (e) V/A, or (f) (V/A)2; where A = surface area of casting, Hf = heat of fusion, Tm = melting temperature, and V = volume of casting?
c
10.16 Solidification shrinkage in casting is defined as which one of the following: (a) liquid contraction during cooling prior to solidification, (b) liquid contraction during cooling and solidification, (c) contraction during the phase change from liquid to solid, or (d) thermal contraction of the solidified casting during cooling to room temperature.?
a
10.17 Metal inserts in the walls of a sand mold cavity designed to remove heat from the molten metal more rapidly than the surrounding sand are called which one of the following: (a) external chills, (b) internal chills, (c) pipes, or (d) sprues?
c,d,e
10.18 A riser in casting is described by which of the following (three correct answers): (a) an insert in the casting that inhibits buoyancy of the core, (b) gating system in which the sprue feeds directly into the cavity, (c) metal that is not part of the casting, (d) source of molten metal to feed the casting and compensate for shrinkage during solidification, and (e) waste metal that is usually recycled?
c
10.19 In a sand-casting mold, the V/A ratio of the riser should be (a) equal to, (b) greater than, or (c) smaller than the V/A ratio of the casting itself?
b
10.2 A factory that performs casting processes is called which of the following (one best answer): (a) casting plant, (b) foundry, (c) ingot-making plant, (d) metal working plant, or (e) molding plant?
a,c
10.20 Which of the following riser types are completely enclosed within the sand mold and connected to the main cavity by a channel to feed the molten metal (two correct answers): (a) blind riser, (b) open riser, (c) side riser, and (d) top riser?
a
10.3 Sand casting is which of the following types of casting process: (a) expendable mold or (b) permanent mold?
a
10.7 In casting processes, a runner is which one of the following: (a) channel in the mold leading from the downsprue to the main mold cavity, (b) worker who moves the molten metal to the mold, or (c) vertical channel into which molten metal is poured into the mold?
b
11.12 Which of the following qualifies as a precision-casting process (two correct answers): (a) ingot casting, (b) investment casting, (c) plaster-mold casting, (d) sand casting, and (e) shell molding?
a,b,d
11.13 Which of the following are metals commonly cast in permanent mold casting (three best answers): (a) aluminum, (b) brass, (c) gold, (d) magnesium, (e) nickel, (f) steel, and (g) tungsten?
a,e
11.14 Which of the following casting processes are permanent mold operations (two correct answers): (a) centrifugal casting, (b) expanded polystyrene process, (c) sand casting, (d) shell molding, (e) slush
a
11.15 In hot-chamber die-casting machines, molten metal is poured into an unheated chamber from an external melting container, and a piston is used to inject the metal under high pressure into the die cavity: (a) true or (b) false?
a,d,f
11.16 Which of the following metals would typically be used in die casting (three best answers): (a) aluminum, (b) cast iron, (c) steel, (d) tin, (e) tungsten, and (f) zinc?
In hot-chamber die-casting machines, molten metal is poured into an unheated chamber from an external melting container, and a piston is used to inject the metal under high pressure into the die cavity: (a) true or (b) false?
True
The Antioch process is similar to plaster-mold casting but uses a mixture of sand and plaster to make the mold: (a) true or (b) false?
True
For which one of the following reasons is a green mold named: (a) green is the color of the mold, (b) moisture is contained in the mold, (c) the mold is cured, or (d) the mold is dry?
moisture is contained in the mold
15.15 In metal extrusion, the extrusion ratio is also known by which of the following terms: (a) area reduction, (b) draft, (c) reduction, or (d) reduction ratio?
reduction ratio
An irregularity in the surface of the casting caused by erosion of the sand during pouring is called which one of the following sand casting defects: (a) penetration, (b) sand blow, (c) sand wash, or (d) scabs?
sand wash EXTRA -> - penetration: fluidity of the liquid metal is high, and penetrates into the sand mold or sand core. - sand blow: a balloon-shaped gas cavity caused by release of mold gases during pouring. - scabs: rough areas on the surface of the casting due to encrustations of sand and metal.
The starting workpiece in steel hot rolling of plate and sheet stock is which of the following
slab
15.4 Furnaces used to heat cast steel ingots to achieve a uniform temperature throughout prior to rolling are called which of the following: (a) annealing furnaces, (b) heat treating ovens, (c) soaking pits, or (d) tempering furnaces?
soaking pits
Which one of the following is the name of the casting process in which molten metal is poured into a rotating mold to produce a tubular part: (a) centrifuge casting, (b) semicentrifugal casting, or (c) true centrifugal casting?
true centrifugal casting
Given that Wm = weight of the molten metal displaced by a core and Wc = weight of the core, the buoyancy force is which one of the following: (a) downward force = Wm + Wc, (b) downward force = Wm - Wc, (c) upward force = Wm + Wc, or (d) upward force = Wm - Wc?
upward force = Wm - Wc
