压力对PCBN复合材料烧结性质的影响及烧结机理研究

Effects of Pressure on the Sintering Properties of PCBN Composite and Sintering Mechanism

在高温高压条件下,通过硬质合金基体的高压原位熔渗法,研究了合成压力对聚晶立方氮化硼(PCBN)复合材料致密度、颗粒形貌及耐磨性的影响。测试结果显示:随着合成压力的提高,PCBN复合材料的致密度和耐磨性均有一定程度的提升。利用扫描电子显微镜和能谱仪对碳化钨合金基体与立方氮化硼的结合界面进行了测试分析。测试结果表明:在高温高压条件下,立方氮化硼聚晶层与碳化钨硬质合金层中的元素彼此扩散、渗透,形成金属过渡层,将二者牢固地结合在一起。

The effects of pressure on the density,particles morphology and abrasion resistance of polycrystalline cubic boron nitride （PCBN） composite were investigated in detail using the melt infiltration method with cemented carbide under high pressure and high temperature conditions. The measured results show that the density and the abrasion resistance of the PCBN composite are enhanced along with the increase of the synthesis pressure. Furthermore,the interface between WC and cBN was characterized using scanning electron microscope （SEM） and energy dispersive spectrometer （EDS）. The results indicate that the elements of WC and cBN interpenetrate each other and generate a transition layer which enables the polycrystalline cBN to bond firmly to the WC substrate.