添加晶粒长大抑制剂对细粒度金刚石复合片烧结的影响

Effect of addition of crystal grain growth inhibitor on sintering of fine-grained diamond compact

研究添加不同晶粒长大抑制剂对晶粒度1μm的细粒度金刚石复合片晶粒异常生长过程及其抑制作用的影响,并对其作为刀具材料的切削结果进行了比较。用扫描电子显微镜(SEM)、能谱仪(EDS)、X射线衍射仪(XRD)、维氏硬度计对细粒度金刚石复合片进行微观组织研究和性能测试,发现TiC与cBN两种晶粒抑制剂均能对晶粒异常长大起到抑制作用,添加cBN能够获得均匀的组织,对两种抑制剂的作用机理进行了探讨。研究中还发现超高压烧结中腔体内局部温度差异过大会导致在较高温区发生晶粒异常长大。

The effect of different crystal grain growth inhibitors on grain abnormal growth process and inhibition of one micron grain size diamond composite is studied, and the cutting result is also compared. Scanning electron microscope(SEM), energy dispersive spectrometer(EDS), X-ray diffrotometer(XRD) and Vickers hardness tester are used to study the microstructure and properties of fine-grained diamond compacts. It is found that TiC and cBN, two grain inhibitors, could inhibit the abnormal grain growth, and the uniform microstructure could be obtained by adding cBN. The action mechanism of the two inhibitors is discussed. It is also found that the abnormal grain growth occurred in the higher temperature area due to the large temperature difference in the cavity.