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利用束流密度50~200 A/cm2、脉冲宽度70 ns的强流脉冲离子束(HIPIB)对WC-Ni硬质合金进行表面辐照处理,测试了辐照WC-Ni硬质合金的微观组织和表面硬度,采用环-块式摩擦磨损试验机、SEM和EDS考察了HIPIB辐照WC-Ni硬质合金的摩擦磨损性能及其磨损机理。结果表明,随束流密度增加,WC-Ni硬质合金表面发生重熔与Ni粘结相的选择性烧蚀,表面重熔致密化,表面硬度显著增加,摩擦系数降低、耐磨性提高,200 A/cm2辐照硬质合金表面熔层约1.6μm,组织明显细化,表面硬度可达14.86 GPa,摩擦系数和磨损率分别降低18%和58%。HIPIB辐照使硬质合金表面磨损机制从原始硬质合金的Ni粘结相优先去除引发WC颗粒剥落去除转变为以均匀微观切削为主的磨粒磨损,这归因于HIPIB辐照WC-Ni硬质合金表面重熔致密化及晶粒细化。
WC-Ni cemented carbide was irradiated by high-intensity pulsed ion beam (HIPIB) with a beam current density of 50-200 A / cm2 and a pulse width of 70 ns. The microstructure of irradiated WC-Ni cemented carbide And the surface hardness of the HIPIB irradiated WC-Ni cemented carbide were investigated by ring-block friction and wear testing machine, SEM and EDS. The results show that as the beam current density increases, the surface of the WC-Ni cemented carbide remelted selectively and the Ni binder phase is selectively ablated. The surface remelting densification, the surface hardness increases significantly, the friction coefficient decreases, the wear resistance increases, The melt layer of 200 A / cm2 irradiated cemented carbide surface is about 1.6μm, the microstructure is obviously refined, the surface hardness can reach 14.86 GPa, and the friction coefficient and wear rate decrease by 18% and 58% respectively. The HIPIB irradiation preferentially removed the cemented carbide surface wear mechanism from the original cemented carbide Ni binder phase, which led to the shift of the WC particles to the abrasive wear which was dominated by uniform micro-cutting. This was attributed to the HIPIB irradiated WC-Ni Carbide surface remelting densification and grain refinement.