Li Yongjun, Li Sicheng, Lv Ran, Qin Jiaqian, Zhang Jian, Wang Jianghua, Wang Fulong, Kou Zili, He Duanwei
(Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China)
Abstract Cubic boron nitride (CBN) composites starting with CBN-Al mixtures were sintered on WC-16 wt% Co substrate under static high pressure of 5.0 GPa at temperatures of 800 to 1 400 ℃ for 30 min. Vickers hardness of the sintered samples increased with increasing CBN content and the highest hardness of 32.7 GPa was achieved for the CBN-5 wt% Al specimens sintered at 1 400 ℃. The reactions between CBN and Al started to occur at about 900 ℃ and the reaction products strongly depended on the Al content, sintering temperature and Co diffused from the substrates according to the x-ray diffraction (XRD) observations. The CBN composite sintered at 1 200 ℃ from a CBN-15 wt% Al mixture showed the best cutting performance.