The phase diagram for pure iron is shown in Figure 5.13. Iron has three different solid phases, called ?, ?, and ?-iron, with different crystal structures. Discuss the behavior of iron as it is heated at different pressures, at 1 atm or at 10^-6atm, for example. Under what conditions can several phases of iron coexist? Does iron have a triple point similar to water's?

A phase diagram for pure iron. The ?, ?, and ? phases are solids with different crystal structure.

Transcribed Image Text:

10° 105 liquid 101 10-3 vapor 10-7 500 1000 1500 2000 2500 temperature [K] 0-1ron 7-iron a-iron pressure [Pa]