High-precision surface grinding of ceramics with superfine grain diamond cup wheels

High-precision surface grinding has been performed on the Si(3)N(4) and Al(2)O(3)-TiC ceramics and Mn-Zn Ferrite using an ultra-precision surface grinder and very fine grain diamond cup wheels, where the maximum depth of cut was 2 mu m and the maximum through feed rate being 100 mm/min. The surface roughness and percent brittle mode area were measured using an atomic force microscopy (AFM). These characteristics were discussed by a parameter "S(max)" defined as S(max) = mu a v(f)/v(s) (mu : successive cutting edge spacing, a : depth of cut, v(f): through feed rate, v(s): wheel speed). With decreasing grain size from #1200 to #16000, the surface roughness Rmax decreases to 20 to 30 nm. Similarly, a remarkable reduction in percent brittle mode area is seen by changing grain size. The effect of dressing stone on the ground surface was also investigated using 3D wheel surface topography.