Kinetics of dynamic recrystallization in Ti-modified 15Cr-15Ni-2Mo austenitic stainless steel

The hot working behaviour of Ti-modified 15Cr-15Ni-2Mo austenitic stainless steel (Alloy D9) was studied by hot compression test at temperatures of 900-1200 degrees C and at strain rates of 0.002-1 s(-1). The progress of dynamic recrystallization (DRX) was modelled by the Avarmi kinetics equation. The flow softening was directly related to the DRX volume fraction and the DRX time was determined by strain rate. For quantification of recrystallization rate, the time corresponding to the DRX fraction of 50% was used. Analysis of the sigmoid-shaped recrystallization curves revealed that the rate of DRX increases with increasing deformation temperature and strain rate. Results of the Avrami analysis were used to predict the DRX flow curves. (c) 2012 Elsevier B.V. All rights reserved