Shape adaptive grinding of CVD silicon carbide

Because of the direct relationship between removal rate and surface roughness in conventional grinding, ultra-precision finishing of hard coatings produced by chemical vapour deposition (CVD) usually involves several process steps with fixed and loose abrasives. In this paper, an innovative shape adaptive grinding (SAG) tool is introduced that allows finishing of CVD silicon carbide with roughness below 0.4 nm Ra and high removal rates up-to 100 mm3/min. The SAG tool elastically complies with freeform surfaces, while rigidity at small scales allows grinding to occur. Since material removal is time dependent, this process can improve form error iteratively through feed moderation.