公开(公告)号：US20220348470A1

公开(公告)日：2022-11-03

申请号：US17766033

申请日：2020-10-02

Applicant: TOMEI DIAMOND CO., LTD.

Inventor： Hiroshi ISHIZUKA (deceased) ,  Yoshiaki ISHIZUKA

IPC: C01B32/28 ,  B01J3/06 ,  C09K3/14

Abstract: [Technical Problem]To provide diamond grits with enhanced friability, and method for the production comprising in combination internal microcracks within the diamond particle and surface irregularities, with or without a layer of non-diamond carbon covering the particle surface.
[Solution to Problem]
The diamond grits of the invention consist of diamond particles synthesized by a static ultrahigh pressure-high temperature process, comprising both microcracks generated within the particles due to the effect of heating, and surface irregularities formed on the particles by oxidizing etching at elevated temperatures.
The production method comprises providing a starting volume of diamond particles, from a synthesizing process in a static ultrahigh pressure-high temperature process, subjecting said diamond particles to a heating process in intimate contact with an oxidizing etchant at a temperature of 800° C. or higher, generating thus microcracks within the diamond particles and also causing to corrode the particle surface thus forming increased surface irregularities, and recovering the treated diamond particles.