Abstract The polycrystalline cubic boron nitride (PcBN) was synthesized in situ under the condition of high pressure (5.5 GPa) and high temperature (1400 °C) with Al-Ti as the cubic boron nitride (cBN) binder. The influence of Al-Ti binder content on the phase composition and micro-structure of the PcBN composites were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results of density and mechanical properties test showed the content of Al-Ti is too small , the reinforcing phase in the sample is less, resulting in insufficient bonding between cBN particles and lower density. The Al-Ti content is too much, bulk Al3Ti is formed in the sample, the binder phase is agglomerated seriously, and the relative density and mechanical properties are decreased. However, when the content of Al-Ti binder is 15-20%, the reinforced phase rod-like TiB2 content in the sample is more, the aspect ratio is moderate, and PcBN can obtain better comprehensive mechanical properties.

中文翻译：

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Al-Ti含量对原位合成PcBN复合材料力学性能的影响

摘要 以Al-Ti为立方氮化硼(cBN)粘结剂，在高压(5.5 GPa)和高温(1400℃)条件下原位合成了多晶立方氮化硼(PcBN)。采用X射线衍射(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS)研究了Al-Ti结合剂含量对PcBN复合材料相组成和微观结构的影响。密度和力学性能测试结果表明，Al-Ti含量过少，试样中的增强相较少，导致cBN颗粒间结合不充分，密度较低。Al-Ti含量过多，试样中形成块状Al3Ti，粘结相团聚严重，相对密度和力学性能下降。然而，