Pitting of a glass-ceramic during polishing with cerium oxide

摘要

The pitting behavior of a transparent spinel-based glass-ceramic polished with a cerium oxide abrasive has been investigated using finishing experiments supported by indentation testing. The pre-ceramed, 'green' glass consistently polished to a surface quality of average roughness (Ra) <1 nm and peak-to-valley <10 nm, as compared to the glass-ceramic which developed pitted surfaces during polishing. Comparison of the two materials showed the glass-ceramic to exhibit a greater amount of subsurface damage than the corresponding glass during indentation testing. The formation of pits is thus attributed to subsurface damage induced during grinding followed by a dissolution reaction with the cerium-oxide-based polishing slurry.