Kinetics of Bainite Formation in 100Cr6 and Similar High-Carbon Steel Grades

This investigation is concerned with quantifying the role of alloying elements in the bainite formation kinetics in 100Cr6 and similar steel grades. Using industrial or laboratory casts, we quantified the influence of Mn, Cr, Si, Mo, C, and Co. For this, dilatometry measurements were carried out at various temperatures between 200 degrees C and 350 degrees C. The influence of the different elements is discussed and compared with that expected from the impact of these elements on the austenite-to-ferrite transformation driving force. It is shown that additions of Co, while indeed having a beneficial influence, can easily be avoided with small adjustments to the austenitizing conditions. The results are used to propose a modified version of the standard 100CrMo7 with a 38 % reduced bainitic reaction duration.