| 摘要 |
PURPOSE:To provide a machined surface of high quality and lengthen the life of a surface plate for polishing a hard brittle material or the like, by planting free abrasive grains in the surface plate made of a soft material, so that the grains have an equal height from the surface of the plate, and processing the surface of the plate to make a hard film thereon. CONSTITUTION:The top 6 of a base plate 2, which is made of a high-purity aluminum alloy and is 300mm. in outside diameter, 100mm. in inside diameter and 10mm. in thickness, is processed by diamond cutting so that the flatness of the top is made not more than 1mu and its roughness is made not more than 0.1mu. Abrasive alumina grains 1 of #3,000 in size are then supplied to grind the top 6 of the plate 2 on a heavy lapping machine made of cast iron, to plant the grains into the top so that the cutting edge height of the grains from the top is made about 0.5mu. The top 6 is then processed for anodic oxidation in a sulfuric acid bath to provide the top with a hard film 5 of about 10mu in thickness and 200-300kg/mm.<2> in HK hardness. A polishing surface plate 7 good in performance and economy is thus manufactured. |
