Al添加量对PcBN复合片显微结构和性能的影响

Effect of Al content on the microstructure and properties of PcBN compact

将cBN微粉添加体积分数为5%、10%、15%、20%的Al粉进行高温高压烧结制备出PcBN复合片。利用X射线衍射仪、扫描电子显微镜分析PcBN复合片的物相组成和显微结构,并研究其磨耗比和抗冲击性能。结果表明,PcBN层主要由cBN晶粒和AlN组成。随着Al粉添加量的增加,AlN的体积分数逐步增加,PcBN复合片的性能也发生相应变化。Al粉添加量为体积分数10%时,PcBN复合片的磨耗比为21 842,冲击次数超过100次,综合性能最好。

Polycrystalline cubic boron nitride （PcBN） compacts were obtained by sintering cubic boron nitride （cBN） powder and A1 powder under 5.0 GPa, 1 300 - 1 400 ℃, with Al content （ volume fraction） being 5 %, 10%, 15%, 20%, respectively. X-ray diffraction and scanning electron microscopy were carried out to investigate the phase composition and microstructure of the PcBN compacts. The abrasion ratio and the impact resistance of the compacts are investigated also. It is revealed that the main phases of PcBN compacts are cBN and AlN. With the increase of the Al content in the starting materials, the AlN content increases correspondingly and the performances of the PcBN compacts change also. When 10% Al （volume fraction） is added, the obtained PcBN compact achieves the optimum properties, with the abrasion ratio being 21 842 and the impact resistance over 100 counts.