金刚石复合片合成中的排杂机理研究

Study on the mechanism of impurity removal during synthesizing of polycrystalline diamond composite

本文利用SEM、X射线衍射等方法研究了以Mo作为密封材料,在高温-高压合成Co基金刚石复合片(PDC)的过程中,PDC中气体及残余Co的排出机制。研究结果表明:Mo可以有效吸收原料素坯在合成过程中排出的气体;合成过程中排出的Co-C熔液均匀包围在PDC周围,形成Co-C富集层;同时Co-C富集层沿Mo晶界扩散,而Mo本身对Co没有吸收作用。

By scanning electron microscope（SEM） and X-ray diffraction（XRD） method,the authors studied the removal mechanism of gas and residual Co in Co-based polycrystalline diamond composite（PDC） sintered under HPHD with Molybdenum capsule as sealing material.It was showed that gas from PDC green body was absorbed effectively by Mo capsule during the high pressure sintering.A Co-C layer around PDC and its diffusion along grain boundaries of molybdenum were observed,which was proved to be formed by residual Co-C melt expelling out from inside PDC during the synthesis.However,Mo capsule did not absorb any Co in its lattice.