'Study of phase transformations during tempering of AISI L6 tool steel by means of dilatometry and high temperature X-ray diffraction'

摘要

The phase transformation and the influence of heating rate during tempering (100°C to 700°C range) for as quenched AISI L6 tool steel are presented in this work. Phase transformations during tempering of the steel were analyzed by means of dilatometry curves recorded during heating from as quenched state. Heating to 700°C was made at different rates (5, 50 and 150°C/s). High temperature X-ray diffraction (XRD) was used to identify the existing phases in the material and to confirm the presence of carbide precipitate and retained austenite. It is possible that changing the rate reduce probability of the occurrence of some phase transformations (transition carbides) in favor of other (cementite carbides). The results of X-ray diffraction showed that is possible observe a precipitation of carbide and cementite into retained austenite.