Foundry Metallurgy — Part 1 MCQs with Explanations

Ferrous alloys, such as cast iron and steel , have very high melting points compared to non-ferrous metals. Die casting machines, including hot and cold chamber types , are typically used for non-ferrous metals like aluminum, zinc, and magnesium, which have relatively low melting points. Hot chamber machines are not suitable for ferrous alloys because the molten metal would corrode or damage the injection components. Cold chamber machines are also unsuitable due to similar issues with extreme temperatures and wear. Ferrous alloys are usually cast using sand casting, investment casting, or shell molding , which can withstand the high temperatures required. Therefore, none of the options listed are appropriate for casting ferrous alloys.

All of these is the correct answer to “Why the quality of sand deteriorates if the same molding sand is used again and again”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

contraction allowance is the correct answer to “Shrinkage allowances is also known as”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

70% sand and 30% clay is the correct answer to “Green sand consists of”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

Blow holes is the correct answer to “The low permeability in sand can cause which of the following defects in casting”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

6.8 is the correct answer to “In a sand casting of a rectangular slab, the thickness of the solidified layer after 2 minutes is known to be 3 cm. Based on Chvorinov's rule, the solidified thickness (in cm) after 4 minutes is”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

shrinkage is the correct answer to “Feed heads, feeders and risers in casting serve to provide sources of molten metal to compensate for”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

All of these is the correct answer to “What are the applications of nodular cast iron”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

Collected in the center of casting is the correct answer to “In centrifugal castings, the impurities are . . . . . . . .”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

0.3 to 0.6mm is the correct answer to “The thickness of shells in shell molding is”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

thickness is the correct answer to “Solidification time of a thin plate casting in a sand mould increases by approximately 4 times with the doubling of”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

P-2, Q-3, R-4, S-1 is the correct answer to “Match the requirement from Group 1 with the suitable casting process from Group 2 . Group 1 Group 2 P. Good surface finish 1. Slush casting Q. Expandable mould 2. Pressure die casting R. Heavy casting 3. Investment casting S. Hollow ornamental casting 4. Sand casting”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

Wet reclamation is the correct answer to “. . . . . . . . process removes fines and foreign matter, partly clay coating from the sand and partially removes the carbonaceous and organic materials from sand grains.”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

Vertical passage is the correct answer to “Sprue in casting refers to . . . . . . . .”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

10.4 is the correct answer to “The shrinkage allowance for 6mm section malleable cast iron is . . . . . . . . mm.”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

Flash is the correct answer to “If two parts of a mould are not joined properly, the casting may have the following defect.”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

40 is the correct answer to “The solidification time for a cube casting having 5 cms side is 10 minutes. Under similar condition of heat transfer, the solidification time, inminutes, for a cube casting having 10 cm side will be”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

only during transformation from liquid to solid is the correct answer to “In a casting, shrinkage occurs”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

investment casting is the correct answer to “A jet engine turbine blade is normally manufactured by”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

P, R is the correct answer to “The casting processes that require expendable moulds are P. Investment casting Q. Low pressure casting R. Shell moulding S. Slush casting”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

liquid state shrinkage and solidification shrinkage is the correct answer to “Riser in a casting compensates for”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

0.05 - 0.1 mm is the correct answer to “What is the length of the flakes in gray cast iron”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

18% is the correct answer to “Loam sand contains . . . . . . . . of moisture”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

After casting solidifies is the correct answer to “The riser is designed such that the melt in the riser solidifies”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

1129° - 1398°C is the correct answer to “What is the solidification temperature of malleable cast iron”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

P-3, Q-2, R-4, S-1 is the correct answer to “Match the defect with appropriate cause. List-I List-II P. Hot tear 1. Inadequate riser Q. Porosity 2. Loosely rammed sand mould R. Sand inclusions 3. Mould restraint S. Shrinkage cavity 4. Gas entrapment”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

Smooth interfacial growth is the correct answer to “When the cooling rate during solidification process is very slow then the growth of nuclei takes place by”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

P-4, Q-1, R-2, S-3 is the correct answer to “Match the features observed in castings listed in Group I with the most appropriate reasons listed in Group II . Group I Group II P. Macrosegregation 1. Inoculation Q. Fine grained structure 2. Gas evolution and shrinkage R. Porosity 3. Temperature gradients and supercooling S. dendrites 4. Density difference and convection currents”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

P, S is the correct answer to “Casting alloys with a large freezing range tend to result in P. shrinkage cavity Q. distributed shrinkage porosity R. liquid metal with poorer fluidity S. liquid metal with superior fluidity”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

cobalt aluminide is the correct answer to “Mould coating material which helps in grain refinement of metal casting is”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

avoid rhomboidity of the casting is the correct answer to “Mould oscillation is used in continuous casting of steels to”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

All of these is the correct answer to “What are the bonding theories”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

all of these is the correct answer to “What are the materials used for pattern making”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

0.4 is the correct answer to “At the mould exit of a continuous caster, the metal consisting of a solidified shell with a liquid metal core exits at the rate of 35 kg S -1 . Given that the latent heat of fusion is 3 × 10 5 J kg -1 and the total rate of heat removal by the mould is 4.2 × 10 6 W, the mass fraction of solid at the mould exit is . . . . . . . . Assume that both while solid and liquid remain at the melting point, they are in the mould.”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

coefficient of expansion is the correct answer to “. . . . . . . . is the tendency of the matter to change its shape, area and volume in response to a change in temperature”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

All of these is the correct answer to “What are the tests done for molding sand”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

grey cast iron is the correct answer to “Riser are not required for casting”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

All of these is the correct answer to “What are the parameters that amount of taper depends”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

riser is the correct answer to “In a sound casting the last liquid to solidify is in the”. This question is standard in competitive examination syllabi for Foundry Metallurgy.

P-3, Q-4, R-2, S-1 is the correct answer to “Match the defects in Group 1 with possible causes in Group 2 . Group 1 Group 2 P. Misruns 1. Sand expansion Q. Shifts 2. Molding materials R. Blowholes 3. Improper heating of metals S. Scabs 4. Molding and core making”. This question is standard in competitive examination syllabi for Foundry Metallurgy.