Quizzes

Sand casting is which of the following types? (a) Expendable mold, (b) permanent mold. (c) neither

(a) Expendable mold,

Which one of the following casting metals is most important commercially? (a) aluminum and its alloys, (b) bronze, (c) cast iron, (d) cast steel, (e) zinc alloys.

(a) aluminum and its alloys

Recrystallization temperature, is (a) the temperature at which a complete recrystallization will occur within the hour. (b) 0.1 to 0.3 of the melting point temperature on absolute scale (c) Both of the above (d) None of the above

(a) the temperature at which a complete recrystallization will occur within the hour.

A riser in casting is not described by which of the following ? (a). casting that inhibits buoyancy of the core, (b) part of mold system which helps directional solidification. (c) metal that is not part of the casting. (d) source of molten metal to feed the casting and compensate for shrinkage during solidification, (e) waste metal that is usually recycled.

(a). casting that inhibits buoyancy of the core,

In a sand casting mold, the V/A ratio of the riser should be which one of the following relative to the V/A ratio of the casting itself? (a) equal, (b) greater, or (c) smaller.

(b) greater than

Work hardening is (a) Increased ductility (b) increased resistance to further deformation (c) both a & b (d) none of the above

(b) increased resistance to further deformation

The microstructure of the metal adjacent to mold cavity tends to be (a). Chilled fine grains (b). Coarse grains (c). randomly oriented (d). a & c (e). b & c

(b). Coarse grains

Recrystallization because of heating result in (a) Formation of new equiaxed grains (b) New strain free grains are formed (c) Both of the above (d) None of the above

(c) Both of the above

The upper half of a sand casting mold is called which of the following? (a) flask, (b) drag. (c) cope

(c) cope

Full annealing is obtained by (a) heating above A3 Acm and allowed to cool in air. (b) heat below A1 and hold there for some time. (c) heating above A1 or A3 and cooling slowly in furnace (d) any of the above. (e) none of the above.

(c) heating above A1 or A3 and cooling slowly in furnace

Examples of point defects are (a) grain boundaries (b) line dislocation (c) vacancy (d) all of the above (e) none of the above.

(c) vacancy

Recrystallization because of heating results in: (a) Decrease the density of dislocation (b) Lower strength (c) Increased ductility (d) All of the above (e) None of the above

(d) All of the above

Chvorinov's Rule states that total solidification time is proportional to which one of the following quantities? (a) (A/V), (b) Hf, (c) Tm, (d) V, (e) (V/A)n where A = surface area of casting, Hf = heat of fusion, Tm = melting temperature, and V = volume of casting.

(e) (V/A)n where A = surface area of casting, Hf = heat of fusion, Tm = melting temperature, and V = volume of casting.

A riser that is completely enclosed within the sand mold and connected to the main cavity by a channel to feed the molten metal is called which of the following (may be more than one)? (a) open riser, (b) blind riser, (c) side riser, (d) top riser. (e) (b) and (c)

(e) (b) and (c)

Ferrite is a solid solution (a) having BCC unit cells. (b) soft, magnetic and ductile. (c) has a max C content of 0. 77%. (d) all of the above. (e) (a) & (b).

A & B

Grain size has the following effects: (a) Coarse grains make the material weaker. (b) Fine grain makes tough material (c) a&b (d) None of the above

A & B

Cementite (a) is an intermetallic compound. (b) very soft and brittle. (c) C content up to 6.8%. (d) (a) and (c). (e) (b) and (c).

A & C

bcc has (a) 48 possible slip systems (b) no close packed planes (c) require large force to produce deformation (e) All of the above

All of the above

Covalent bonds and Ionic bonds result in a: a. formable metals. b. Brittle structure. c. A structure of poor conductivity. d. (a) & (c) e.(b) & (c).

B & C

Austenite is (a) BCC (b) Very strong and hard to form. (c) has a Carbon solid solubility of up to 2.11%. (d) (a) and (b) (e) (a) and (c)

C. Has a Carbon solid solubility of up to 2.11%

Iron, depending on the temperature, may exist in of the following unit structure: (a) bcc & hcp (b) fcc & hcp (c) fcc & bcc (d) Any of the above (e) None of the above

C. fcc & bcc

At the eutectoid temperature (a) If cooling rate is high a fine pearlite is precipitated. (b) if cooling rate is low a bainite is precipitated (c) both of the above. (d) none of the above.

D. None of the above

A grain is unlike a crystal, in that the grain has to compete with neighboring grains for space to grow in. T/F

False

A slowly cooled austenite will precipitate Martensitic structure. T/F

False

At room temperature, atoms of a pure metal for their relative spatial arrangement, do not observe any particular arrangement. T/F

False

Brinell is good for microhardness testing. T/F

False

The Normal stress and engineering strain plots obtained from tensile testing provide an accurate measure of material behavior in the high plastic deformation range of metal forming processes T/F

False

Ferrous or nonferrous are subject to different heat treatment procedures. T/F

True

Grain boundaries have a direct bearing on the resulting macro mechanical behavior. T/F

True

Impact loading test gives a good measure of toughness. T/F

True

Rockwell C is more suitable for testing hard material than Brinell. T/F

True

The steel eutectoid temperature is the temperature at which all of the remaining austenite transforms to pearlite T/F

True

In casting, a flask is which one of the following? a. beverage bottle for foundrymen, b. box which is composed of cope and drag, c. container for holding liquid metal, or d. metal which extrudes between the mold halves

b. box which is composed of cope and drag

During pouring of molten metal oxides forming a. are dross or slag b. can be reduced or eliminated by use of flux c. can be reduced or eliminated by use of vacuum d. all of the above is true e. none of the above

b. can be reduced or eliminated by use of flux

Pure metals usually have somewhat limited properties that can be enhanced by (a) alloying. (b) mechanical deformation. (c) both of the above. (e) none of the preceding.

both of the above

Poor fluidity can lead to a. miss runs b. cold shuts c. both of the above d. none of the above

c. both of the above

If the molten metal speed a. is high it may cause erosion of mold wall b. is low it may cause miss runs and cold shuts c. both of the above are true d. none of the is above

c. both of the above are true

In foundry work, a runner is which one of the following? a. vertical channel into which molten metal is poured into the mold. b. foundryman who moves the molten metal to the mold, or c. channel in the mold leading from the down sprue to the main mold cavity, d. None of the above

c. channel in the mold leading from the down sprue to the main mold cavity

Tensile testing used very widely because: a. it is none destructive. b. results are directly applied to the general case of mechanical stressing c. gives reasonable measure of strength and toughness of the material. d. all of the above e. none of the above

c. gives reasonable measure of strength and toughness of the material.

Properties of materials depend on (a) micro structure (b) composition. (c) processing history (d) all of the preceding. (e) none of the above.

d. All of the above

The results of impact testing are sensitive to: a. Notch size and shape. b. Temperature. c. Impact speed and manner of loading. d. All of the stated above. e. None of the above.

d. All of the above

Which of the following affect faster cooling? a. Chilling in Pomona's fresh breeze. b. Quenched in mountain spring water. c. Quenched in low cholesterol oil. d. Quenched in the pacific salty water.

d. Quenched in the pacific salty water.

The factors affecting the fluidity of a molten metal during pouring into a mold cavity? a. pouring temperature, b. the type of sand binder used c. heat transfer to the surroundings. d. a & c e. b&c

d. a & c

Identify some of the important advantages of casting processes. a. complex part geometries are possible; b. some casting operations are net shape processes, meaning that no further manufacturing operations are needed to accomplish the final part shape; c. very large parts are possible; d. applicable to any metal that can be melted; e. All of the above

e. All of the above

The limitations and disadvantages of casting? a. limitations on mechanical strength properties; b. porosity; c. poor dimensional accuracy d. Safety hazards and environmental problems. e. All of the above

e. All of the above

The sources of contraction in a metal casting after pouring. a. contraction of the molten metal after pouring, b. solidification shrinkage during transformation of state from liquid to solid, and c. the compressive forces applied by the contracting mold cavity. d. a& b e. a & c

e. a & c

Casting quiz

qiuz #2

Heat transfer quiz

quiz #1