【摘要】 为了提高塑料模具钢的预硬化质量,按性能要求,研究了P20钢大锻件的预硬化工艺,并用JEM-200CX电更多还原

【Abstract】 In order to improve prehardened quality of plastic mold steel,prehardening process of big forged piece of the P20 steel was studied according to property request and its microstucture was observed with the JEM200CX electronic microscope.The results show that the martensite turned into the even and small tempered troostite after tempered and the tempered bainite was coarse.It was difficut for the big P20 steel to be quenched thoroughly,so the surface layer acquired the martensite but central part got the conformity structure of martensite and pearlite.In order to acquire even prehardening property,the big forged piece should be quenched thoroughly and then tempered at the high temperature so that the even tempered troostite can be got.更多还原