In this paper, five kinds of PCBN composite with different cBN volume percentages (vol%) were synthesized using cBN as raw materials, TiCN and Al as binders, and high temperature and ultrahigh pressure conditions. The microstructure, hardness, abrasion ratio and cutting performance of the synthesized PCBN composite was tested. By observing the wear morphology of the front and rear cutting surfaces of the PCBN tool, the failure wear mechanism of the tool was analyzed. The cutting performance of hardened bearing steel GCr15 processed by PCBN tool was studied in terms of volume content of cBN, cutting parameters and roughness of the processed surface. The results show that the binder of the PCBN composite is evenly distributed around the cBN particles and has good compactness. The hardness of PCBN composite increases with the increase of cBN volume percentage (vol%); PCBN tools with high cBN volume percentage (vol%) have a longer service life. SEM and EDS line scans analysis results show that the wear mechanism of PCBN tool high-speed cutting hardened bearing steel GCr15 is the result of multiple wear mechanisms such as bond wear, diffusion wear, and oxidation wear local spalling.

本文以cBN为原料，TiCN和Al为结合剂，在高温超高压条件下合成了5种不同cBN体积百分比（vol%）的PCBN复合材料。测试了合成的PCBN复合材料的显微组织、硬度、磨损率和切削性能。通过观察PCBN刀具前后切削面的磨损形态，分析了刀具失效磨损机理。从cBN的体积含量、切削参数和加工表面粗糙度等方面研究了PCBN刀具加工硬化轴承钢GCr15的切削性能。结果表明，PCBN复合材料的粘结剂均匀分布在cBN颗粒周围，具有良好的致密性。PCBN复合材料的硬度随着cBN体积百分比（vol%）的增加而增加；cBN体积百分比（vol%）高的PCBN刀具使用寿命更长。SEM和EDS线扫描分析结果表明，PCBN刀具高速切削淬硬轴承钢GCr15的磨损机制是结合磨损、扩散磨损、氧化磨损局部剥落等多种磨损机制的结果。