Study on the finishing capability and abrasives-sapphire interaction in dry chemo-mechanical-grinding (CMG) process

•Dry chemo-mechanical grinding is proposed to finish sapphire substrate.•Chromium oxide is suggested to be another potential abrasive candidate to finish sapphire.•Besides of surface quality, the characterization of subsurface integrity is highlighted.•It is the first time to demonstrate the solid phase interaction between chromium oxide and sapphire.