... not expensive.2. At present, it is widely used in machinery, aviation and space, optic glass, ceramics, electronics, petroleum, geology, military ... lapping and polishing such hard materials as cemented carbide, ceramics, gems, optical glass.Generally,W0-0.5 to W6-12 micro-powder is used ... for polishing, W15-10 to W22-36 for lapping,W12-22and coarser for finishing.4 ...