Drilling Mechanism Investigation on SiC Ceramic Using Diamond Bits
Chao Gao*, Guorong Wu, Sheng Wang
Identifiers and Pagination:Year: 2017
First Page: 25
Last Page: 36
Publisher Id: TOMEJ-11-25
Article History:Received Date: 20/12/2016
Revision Received Date: 03/03/2017
Acceptance Date: 03/04/2017
Electronic publication date: 30/06/2017
Collection year: 2017
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
SiC ceramic have been widely used in the fields of armor protection, but SiC ceramic is one of the difficult-to-machine material for its high hardness and low fracture toughness.
This paper presents an investigation of drilling mechanism on SiC ceramic using diamond bits.
Based on the theory of indentation fracture mechanics model, cutting average load model and cutting average depth model for single particle were established, theory analysis of drilling mechanism was carried out; through scanning electron microscope (SEM) observation, experimental removal mechanism was discussed.
Results and Conclusions:
The results show that, brittle fracture is the dominant way for SiC ceramic’s removal mechanism, plastic deformation always exists during the drilling process. Brittle fracture includes cleavage fracture, transgranular fracture, intergranular fracture, material peeling off and grain boundary breakage; resintering and recrystallization happen under the joint action of grinding forces and grinding heat in the contact area, where plastic flow characteristics also appear; powdering removal is accompanied by the drilling process; cleavage fracture and transgranular fracture occur on intergranular pores and grain boundary; residual cracks are found in the drilling surface resulted by drilling stress and high temperature.