Question

when iron is heated above 900°c, it changes from BCC to FCC unit cell assuming that atomic radius does not change.calculate ratio of density of BCC to FCC unit Cell?

Answer 1

Iron represents perhaps the best-known example for allotropy in a metal. At atmospheric pressure, there are three allotropic forms of iron: alpha iron (α) a.k.a. ferrite, gamma iron (γ) a.k.a. austenite, and delta iron (δ). At very high pressure, a fourth form exists, called epsilon iron (ε) hexaferrum. Some controversial experimental evidence exists for another high-pressure form that is stable at very high pressures and temperatures.[1]