Chemo-mechanical grinding by applying grain boundary cohesion fixed abrasive for monocrystal sapphire

Abstract

This paper presents a novel fixed abrasive tool namely grain boundary cohesion fixed abrasive pellet (GBCFAP) which is able to provide higher finishing efficiency as well as better surface/subsurface quality of sapphire substrate during the chemo-mechanical grinding (CMG) process. The manufacturing procedures of GBCFAP are introduced in detail in this paper. It is found that the sintering temperature plays an important role to the strength of GBCFAP, and the strength of GBFCAP could be flexibly adjusted by sintering temperature. The experiment result suggests that the recommended sintering temperature ranges from 600 to 650 °C according to current CMG conditions. Meanwhile, comparing with conventional resin bound CMG wheel, 600 °C sintered GBCFAP CMG wheel performs better in terms of material removal rate and surface/subsurface quality since the chemical effect and mechanical effect during CMG process are well balanced. Meanwhile, the solid phase reaction between sapphire and Cr2O3 abrasive is demonstrated by TEM observation and XPS quantification.