Microstructure evolution and mechanical property enhancement of high-Cr hot work die steel manipulated by trace amounts of nano-sized TiC

Simultaneously increasing the strength and ductility of hot work die steels is significant interest for broad applications. The in-situ development a nano-phase in promising method achieving this objective. However, little success has been reported so far. In study, trace amounts TiC nanoparticles were successfully introduced into high-Cr steel (HHD) through an innovative using nano-TiC/Al master alloy. Upon adding 0.02 wt% nano-TiC, incompletely recrystallized ferrite phase was observed HHD containing nano-TiC. Moreover, more globular pearlite distributed at grain boundaries with nano-TiC than unmodified HHD. added provided nucleation sites γ-Fe dendrites prevented growth during solidification austenitizing heat treatment. Furthermore, it noticeably increased precipitation uniform nanoscale chromium carbides significantly refined quenching tempering. Finally, simultaneously enhanced toughness After 1353 K tempering 833 K, yield strength, tensile strain, impact 1330 MPa, 1620 14.4 % 460 J/cm2, respectively, which are all higher those without