Flow Behavior and Evolution of Microstructure during Hot Deformation for a High Mo Stainless Steel

The mechanical behaviors of high Mo austenitic stainless steel 00Cr20Ni18Mo6CuN] have been investigated using the methods of hot compression simulation test on the Thermecmaster-Z simulator. The dynamic recrystallization kinetic equation was established, Avrami coefficient n lies in between 0.9～2 depending on deformation parameters. A perfect flow stress model considering dynamic recrystallization was also established. Dynamic recrystallization tends to complete at 1050℃ and high strain rate, but at temperature below 950℃, it is hard to occur. Double-stage interrupt compression tests were carried out. Activation energy for static and metadynamic recrystallization have been obtained respectively (QSRX=483.7, QMDRX=253.5 k J/mol). Avrami coefficient of MDRX is about 0.5, and t0.5-kinetics equations of SRX and MDRX have also been constructed. The evolution of microstructures during interrupt compression deformation was investigated. Static and metadynamic recrystallizationis essential to improve plasticity, at temperature above 1000℃ increasing interpass time has advantage for static and metadynamic recrystallization.