Engineering Materials

A. at which crystals first start forming from molten metal when it is cooled
B. at which new spherical crystals first begin to form from the old deformed one when a strained metal is heated
C. at which change of allotropic form takes place
D. at which crystals grow bigger in size
E. at which crystals are destroyed on heating

A. room temperature
B. above melting point
C. between 1400°C and 1539°C
D. between 910°C and 1400°C
E. none of the above

A. below 10°K
B. above 100°K
C. around 0°C
D. around 100°C
E. above 1000°C

A. alpha iron, beta iron and gamma iron
B. alpha iron and beta iron
C. body centred cubic a-iron and face centred cubic a-iron
D. alpha iron, gamma from and delta iron
E. none of the above

A. room temperature
B. near melting point
C. between 1400°C and 1539°C
D. between 910°C and 1400°C
E. none of the above

A. ferrite
B. pearlite
C. anstenite
D. ferrite and cementite
E. ferrite and pearlite

A. 0.2%
B. 0.8%
C. 1.3%
D. 2%
E. 6.3%.

A. in a random manner
B. in a haphazard way
C. in circular motion
D. back and forth like tiny pendulums
E. do not move

A. 770°C
B. 910°C
C. 1440°C
D. 1539°C
E. none of the above

A. body centred cubic
B. face centred cubic
C. hexagonal close packed
D. cubic structure
E. orthorhombic crystal