Metman, regarding my previous question about the effects of increasing the austenitizing T from 800 C to 900 C, how did you know you were above the recrystallization T?
I believe recrystallization starts at 727C for carbon steels. I hope metman agrees with me on this. I thought it could be read off the phase diagram of Fe-Fe3C.
alwilliams,
The lower critical temperature where phase change occurs from BCC to FCC corresponds to the Rx temp. In this case 1333F as I recalll which is close to 727C(1341F). Also this above .35X3257R = 1139F for Iron but Steel has a lower melting point than Iron.
Recrystallization can happen at temperatures below the austenite transformation temperature. I would say it is guaranteed, however, that if you heat above the austenitization temperature, you will "recrystallize", since you are transforming crystal structure.