硬质合金高压熔渗制备聚晶立方氮化硼复合片

Preparation of Polycrystalline Cubic Boron Nitride Compact by Cemented Carbide High-Pressure Infiltration

在高温高压条件下(HPHT,5.2GPa,1450℃),通过硬质合金基体的高压原位熔渗法,制备了质地均匀的Φ15×5mm的聚晶立方氮化硼(PcBN)复合片。采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、能谱仪(EDS)等考察了PcBN复合片的组织形貌及物相成分,并对其界面复合机理进行了探讨。实验结果表明,硬质合金(WC-Co)基体中WC及Co通过熔渗扩散到立方氮化硼(cBN)层,通过WC、MoCoB、Co3W3C等粘结相,实现了PcBN复合片的界面复合,PcBN层形成致密的"混凝土"结构。

Under high temperature and high pressure conditions （HPHT, 5.2GPa, 1450℃）,homogeneous Polycrystalline Cubic Boron Nitride （PcBN）compact ofΦ15 ＆#215; 5 mm has been synthesized through the cemented carbide high pressure in situ melting infil-tration method.The structure morphology and phase composition of PcBN compact has been investigated through scanning electron microscope （SEM）,X-radial Diffractometer （XRD）and Energy Disperse Spectroscopy （EDS）.It＆#39;s mechanism of composite interface has also been discussed.The experiment result shows that the WC and Co in the cemen-ted carbide （WC-Co）substrate spread into Cubic Boron Nitride layer through melting in-filtration.And the binding phase of WC,MoCoB and Co3 W3 C facilitate the interface re-combination of the PcBN compact,hence a compact＆quot;concrete＆quot;structure has been formed on the PcBN layer.