屏蔽杯材质对高cBN含量PcBN复合片的影响

The effect of shield cup materials on polycrystalline cubic boronnitride compacts with high cBN content

通过改变高cBN含量PcBN复合片屏蔽杯的材质(锆杯、钼杯和铌杯),在合成温度为1400℃~1500℃、压力5~5.5 GPa和烧结时间20~25 min条件下烧结成型。经后加工平面磨及外圆磨后,对比不同屏蔽杯材质对合成得到复合片的缺陷及抗冲击韧性所带来的变化。试验结果表明,针对高cBN含量PcBN复合片的合成,应选择熔点更高的钼和铌作为屏蔽材料,既避免高温对复合片边缘过烧,拓宽合成区域,提高合成稳定性和抗冲击韧性,又降低制刀过程中聚晶层开裂现象,显著提高产品成品率和客户满意度。

Under the conditions of synthesis temperature of 1400℃~1500℃,pressure of 5~5.5 GPa and sintering time of 20~25 min,polycrystalline cubic boron nitride(PcBN)compacts with high cBN content are formed by changing the shield cup materials(zirconium,molybdenum and niobium).After surface grinding and cylindrical grinding,the effects of different shielding cup materials on the defects and impact toughness of PcBN compacts are compared.The experimental results show that molybdenum and niobium with higher melting point should be selected as shielding materials for the synthesis of PcBN composites with high cBN content,which not only can avoid overburning on the edge of composites at high temperature,broaden the synthesis temperature area,improve the synthesis stability and impact toughness,but also reduce the cracking phenomenon of polycrystalline layer during the cutting process,and significantly improve the product yield and customer satisfaction.