Precision grinding with CVD diamond coated grinding wheels

Advanced results are presented on the manufacturing and application of CVD diamond grinding wheels for grinding of optical glass, cermet and alumina. Since bonded diamond grinding wheels are restricted concerning very fine grain sizes a new grinding layer technology is under development. A polycrystalline diamond layer with a high adhesion strength to the wheel body is deposited by chemical vapour deposition (CVD). The sharp edges of the crystallites act as cutting edges for grinding. Crystallite protrusions of a few microns down to below one micron can be achieved easily with this technique. It was shown that by using CVD-diamond coated grinding wheels a high material removal rate and a high ground surface quality with surface roughness in the nanometer range can be achieved. The CVDdiamond layers have higher wear resistance compared to conventional metal and resin bonded diamond wheels. Moreover, it was demonstrated for the first time that a resharpening of worn CVD diamond layers is possible.