Effect of Additives in Synthetic Polycrystalline Diamond on Its Graphitization Resistance
Peng Yingcong Zhang Xingdong Li Boxun Cao Yang Ji Xiaoyang (Institute of Materials Science and Technology, Sichuan University,Chengdu, 610064)
An experimental study of the graphitization resistance of synthetic polycrystalline diamonds is reported in this paper, Two groups of specimens were chosen. (1) synthetic potycrystalline, diamonds each containing ore kind of the alloy additives Co-Fe, Ni-Ti, Co-Fe-Zr and Ti-Si-B; and (2) the Co-Fe and Ni-Ti containing synthetic diamonds from which the Co, Fe and Ni atoms have been removed Phase component analyses and wear resistance tests were carried out for these specimens before and after they were subjected to heat treatment at 1150℃ in a reducing atmosphere. The experimental results show that the lower graphitization resistance of synthetic polycrystalline diamonds, as compared with the synthetic diamond grains is mainly due to the direct contact of the catalytic transition metals or alloys existing in the synthetic polycrystalline diamond with the surfaces of the synthetic diamond grains.