1. at which crystals first start forming from molten metal when it is cooled
2. at which new spherical crystals first begin to form from the old deformed one when a strained metal is heated
3. at which change of allotropic form takes place
4. at which crystals grow bigger in size
at which new spherical crystals first begin to form from the old deformed one when a strained metal is heated
1. stages at which allotropic forms change
2. stages at which further heating does not increase temperature for some time
3. stages at which properties do not change with increase in temperature
4. there is nothing like points of arrest
stages at which allotropic forms change
1. has a fixed structure under all conditions
2. exists in several crystal forms at different temperatures
3. responds to heat treatment
4. has its atoms distributed in a random pattern
exists in several crystal forms at different temperatures
1. austenite
2. pearlite
3. ferrite
4. cementite
ferrite
1. alpha iron, beta iron and gamma iron
2. alpha iron and beta iron
3. body centered cubic a-iron and face centered cubic a-iron
4. alpha iron, gamma from and delta iron
alpha iron, gamma from and delta iron
1. face-centered cubic lattice
2. body-centered cubic lattice
3. hexagonal close-packed lattice
4. all of the above
face-centered cubic lattice
1. ferrite
2. pearlite
3. anstenite
4. ferrite and cementite
ferrite
1. molecular change
2. physical change
3. allotropic change
4. solidus change
allotropic change
1. in a random manner
2. in a haphazard way
3. in circular motion
4. back and forth like tiny pendulums
back and forth like tiny pendulums
1. body centered cubic
2. face centered cubic
3. hexagonal close packed
4. cubic structure
face centered cubic