Cr12MoV模具钢搅拌摩擦加工超细晶表面层性能研究

Properties of xiltrafine-grained surface layer for Cr12MoV die steel by friction stir processing

采用不同旋转速度进行搅拌摩擦加工Cr12MoV模具钢超细晶表面层的制备,并测试分析超细晶表面层的组织与性能。结果表明,采用搅拌摩擦加工方法可在Cr12MoV模具钢表面制备出晶粒尺寸为4~8μm的超细晶表面层。与常规氮化处理Cr12MoV模具钢相比,采用搅拌摩擦加工处理的Cr12MoV模具钢磨损体积减小68%、冲击吸收功增大72%。随旋转速度从200 r/min增大至1 000 r/min,超细晶模具钢的晶粒先细化后粗化,耐磨损性能和抗冲击性能均先提高后下降。搅拌摩擦加工时的旋转速度优选为600 r/min。

The ultrafine-grained Cr12 MoV die steel was prepared by friction stir processing under different tool rotation rates,and the microstructure and properties were analyzed. The results show that the grain size of the ultrafine-grained Cr12 MoV die steel is4-8 μm,the wear volume decreases by 68% and the impact absorption energy increases by 72% compared with conventional nitriding treated Cr12 MoV die steel. As the rotation rate increases from 200 r/min to 1 000 r/min,the grain size is refined and then roughened,both the wear resistance and impact property first increase and then decrease. The optimized rotation rate is 600r/min.