Effect of Austenizing Temperature and Time on Microstructure and Mechanical Properties of Cr12MoVNbRE Steel

Abstract

A new-type of Cr12MoVNbRE die steel was designed and investigated. The phase transition temperature was measured by dilatometer. Effects of austenizing temperature and time on the microstructure and mechanical properties of the Cr12MoVNbRE die steel were studied. The results show that the hardness decreases with the increasing austenitizing time. As for the austenitizing temperature, it increases firstly, and then decreases when the austenitizing temperature increases. The most suitable austenitizing temperature and time are 1010 °C and 20 min respectively. The high hardness of the Cr12MoVNbRE die steel is mainly attributed to the martensite with high alloy content and fine uniformly dispersed carbides.

Austenite stability and M2C carbide decomposition in experimental secondary hardening ultra-high strength steels during high temperature austenitizing treatments

“…; prior austenite grain size, morphology of martensitic lath structure, volume fraction of primary carbides (carbides retained after austenitizing treatment are called primary carbides whereas carbides formed during tempering are called secondary carbides), amount of alloying elements dissolved in the austenite and the amount of retained austenite [4][5][6][7][8]. Higher the austenitizing temperature, a greater amount of alloying elements is expected to be dissolved in the austenite [9]; therefore full potential of these alloying elements can be exploited during subsequent quenching-tempering process in which secondary hardening precipitates form. However higher austenitizing temperatures also results in increasing the prior austenite grain size [7,[10][11][12][13][14].…”