Influence the abrasive type and the magnitude of the contact pressure on lapping of ceramics

This article summarizes the methods of processing of ceramic materials. For processing technical ceramics shows the process of grinding and lapping are described stage machining. In a first step, ground off up to 80 % of the material to be removed, the processing is performed at high speeds coarse tool. At the second grinding step of grinding volume of the material decreases, the second stage of processing is conducted by abrasion with finer grains. The third stage - made diamond lapping, abrasive micropowders, pastas desired granularity. Often, after the lapping stage polishing operation, while achieving accuracy class 1-3 and low roughness. Investigated lapping detail made of a material on the basis of oxide ceramics brand VSH-75. The work found that the performance of the diamond micro-powder in 15-30 times more compared with the performance of micron powders based Al2O3 and SiC. With increasing granularity of the grit increases removal material and roughness surface. To get the parameter of roughness Rz = 0.8 mm, it is recommended to use synthetic diamond micropowder ASM20. Also investigated the influence of the contact pressure in lapping in the range of 25 to 150 kPa. By increasing contact pressure of 25 to 50 kPa increases the magnitude of the total removal, significantly decreases the specific consumption of diamond and reduced roughness processed surface. Further increases in the contact pressure to 150 kPa, has a less marked effect on the parameters, and the tool surface defects appear and the scratches that seriously affects the appearance of the tool. Optimal contact pressure in lapping ceramic on cast iron lapping SCH-28 should be considered 50…100 kPa.