热等静压法制备NbC颗粒增强45CrMoV复合材料的组织与性能

Structure and peoperties of HIP NbC particulate reinforced 45CrMoV composite

采用机械球磨和热等静压(hot isostatic press,HIP)相结合的方法制备NbC颗粒增强45CrMoV弹簧钢基复合材料(NbCp/45CrMoV),观察该材料的显微组织、增强颗粒分布和界面结合情况,检测其相对密度、硬度、拉伸性能和摩擦磨损性能,并探讨其断裂行为和磨损机理。结果表明,NbCp/45CrMoV复合材料的组织均匀细小,NbC颗粒均匀地弥散分布在基体之中,且与基体界面结合良好,相对密度达到99%以上。与45CrMoV弹簧钢相比,该材料的硬度和弹性模量增大,分别为44 HRC和208 GPa,抗拉强度略有降低,为1 250 MPa;伸长率由11%减小到2%;耐磨性能大幅提高,特别是在高载荷下,例如700 N时,质量磨损只有HIP 45CrMoV的1/4,摩擦因数有所增大。

NbC particulate reinforced spring steel matrix composite（NbCp/45CrMoV） was prepared by hot isostatic pressing（HIP）,and its physical/mechanical properties had been investigated,including observing the microstructure,NbC distribution and the bonding interface of the composite,measuring the density,hardness,tensile strength,wear resistance of the composite,and analyzing the fracture behaviour and wear mechanism of the composite.Study results show that the composite has fine microstructure,uniform NbC distribution and good interface bonding between 45CrMoV matrix and NbC particles.The relative density,tensile strength,elongation,hardness,elastic modulus of the composite are 99%,1 250 MPa,2%,HRC 44,208 GPa,respectively.The wear resistance of the composite has greatly enhanced,especially under high load,the wear loss of NbCp/45CrMoV composite is only one quarter of the HIP 45CrMoV under load of 700 N,and the friction coefficient becomes greater.