Polishing behavior and surface quality of alumina and alumina/silicon carbide nanocomposites

The response of Al2O3 and Al2O3/SIC nanocomposites to lapping and polishing after initial grinding was investigated in terms of changes in surface quality with time for various grit sizes. The surface quality was quantified by surface roughness (R-a) and by the relative areas of smooth polished surfaces as opposed to rough as-ground areas. Polishing behavior of the materials was discussed in terms of SiC content and grain size. It was concluded that nanocomposites are more resistant to surface damage than Al2O3, and this behavior does not depend on the amount of SIC in the range 1-5 vol%, SiC addition greater than or equal to 1 vol% is enough to produce a noticeable improvement in surface quality during lapping and polishing.