On the question of nitride ceramics processing with soft abrasive grain

Abstract

Development of modern mechanical engineering relates to development and introduction of new materials and progressive technological processes of their treatment. Unique properties of ceramics make it possible to use ceramics in different areas of engineering that is as cutting instruments, details of machines, devices, radioelectronic apparatus. Due to high hardness machining of ceramics is possible only with the use of synthetic diamonds, but synthetic diamonds are rather expensive that is why it is necessary to use cheaper materials instead of expensive synthetic diamonds. To improve the treatment of ceramics it is necessary to study the rules and regularities of the complicated and multivariable polishing process. Productivity, surface quality, wear and firmness of instrument result from the properties of ceramics, diamond instrument performance, modes and from the technological features of the equipment. Providing high quality of accurate ceramic details surface is a difficult technical task. Besides roughness that results from the conditions under which the instruments are used it is highly necessary to have neither microcracks nor microcavities. As ceramic materials are fragile, all ceramic ware has a tendency to shearing off under load at cutting and polishing. Point loading at low yield makes the ceramics crumble out under strong mechanical and thermal loading of the diamond grains. And there forms a ditch, its width exceeding the area of the diamond grain and the material collision. The article describes an attempt to treat nitride ceramics with a soft abrasive, the ceramics being much harder than the abrasive. It has been supposed that a soft abrasive wearing out does not stop removing material from the ceramic surface. It has been proved graphically and mathematically, that removing material does not stop