聚晶金刚石比磨削能的试验研究

EXPERIMENTAL STUDY ON THE SPECIFIC GRINDING ENERGY OF POLYCRYSTALLINE DIAMOND

本文通过试验研究了PCD材料的比磨削能u与磨削工艺参数的关系。结果表明,随磨削速度vs的提高比磨削能u的变化规律为:低速区,u值较小且增长速度缓慢;中速区,u值快速提高;高速区,u值达一稳态值。随切入深度ap的提高比磨削能u的变化规律为:ap小于某值时,u值快速增长;ap大于某值时:u直达一稳态值。随刀架静刚度Fa的提高比磨削能u的变化规律为:Fa低于某值时,u值以较快速度增长;Fa高于某值时,u值达一稳态值。同时通过分析可知,PCD的磨削机理与比磨削能u存在一定的关系。u值较小时,以疲劳脆性去除为主;u值较大时,随u值的增大疲劳脆性去除的比例减小、机械热去除及热化学去除的比例增大;u值达稳态时,以机械热去除及热化学去除为主,基本不发生疲劳脆性去除。

Through some tests, this paper investigated the relationship between the specific grinding energy u and the grinding process parameters. The test results demonstrated the varying law of u with the grinding velocity vs, the cutting deep ap and the static stiffness of tool holder Fa. The varying law of u with vS is that in low speed range, u is small and increases slowly, and in middle speed range, u increases very quickly, and in high speed range, u reaches some stable value. The varying law of u with ap is that when ap is smaller than a certain value, u increases very quickly, and when ap is larger than a certain value, u reaches a stable value. The varying law of u with F. is that when Fa is lower than a certain value, u increases quickly, and when Fa is higher than a certain value, u reaches a stable value. Also in the paper, the relationship of the PCD grinding mechanism with u is given. When u is small, the fatigue-brittle removal takes a main part in material removing, and the thermo-mechanical removal and the thermo-chemical removal gradually play a main action, and the fatigue-brittle removal decreases with the increasing of u; when u reaches a stable value, the thermo-mechanical removal and the thermo-chemical removal have completely played a main action in the material removing and the fatigue-brittle removal does not happen basically.