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用Ｘ射线衍射、电子探针、透射电镜和光学金相方法，研究了钨钴类硬质合金渗硼层的硬化机理。结果表明：ａ）钨钴类硬质合金渗硼导致显微组织发生变化，碳化钨颗粒的间距增大，棱角变圆，相对量减少。ｂ）ＹＧ８渗硼层中发现了钴的硼化物和钨的硼化物，前者的硬度为１４００～２０００ＨＶ；后者的硬度为２０００～３１００ＨＶ．ｃ）电子探针分析表明：渗硼过程中在硼的扩散层内元素重新分布，钴向内迁移，钨和碳向外扩散．ｄ）ＹＧ８硬质合金渗硼层硬度为２７００ＨＶ以上，耐磨性明显提高。渗硼工艺可用于硬质合金高速拉拔模具。
The hardening mechanism of the boronizing layer of tungsten-cobalt-based cemented carbide was studied by X-ray diffraction, electron probe, transmission electron microscopy and optical metallography. The results show that: a) the microstructure changes when arsenic is infiltrated by tungsten-cobalt-based cemented carbide, the distance between tungsten carbide grains increases, and the edge angle becomes round and the relative amount decreases. b) borides of cobalt boride and tungsten are found in the boron nitride layer of YG8, the former has a hardness of 1400-2000 HV and the latter has a hardness of 2000-3100 HV. c) Electron probe analysis showed that during the boronizing process, the redistribution of elements in the diffusion layer of boron, the inward migration of cobalt and the outward diffusion of tungsten and carbon. d) YG8 carbide boronizing layer hardness of 2700HV or more, significantly improved wear resistance. Boronizing process can be used for carbide high-speed drawing die.