Study On The Fabrication Process Of Ceramic Corundum Abrasive

Ceramic corundum abrasive is a new type abrasive prepared through sol-geltechnique, which exhibits excellent properties such as high hardness, self-sharpeningand ultrafine grains etc. In this research, new ceramic corundum abrasive wasobtained through pressureless sintering method with precursor made by sol-gel route.The effects of additive system, additive molar ratio and sintering method on themicrostructure, single particle compressive strength of ceramic corundum abrasiveswere systematically investigated by scanning electron microscope （SEM）, diamondsingle particle compressive strength tester and X-ray diffractometer.The results revealed that the microstructure and properties of abrasives wereinfluenced greatly by the additive system, additive molar ratio and sintering methodemployed during the preparation process. Different binary additives had differenteffects on the grain size, density and single particle compressive strength of ceramiccorundum abrasives. Among the binary additives, the abrasives obtained withTiO₂/SiO₂or CuO/SiO₂additive systems exhibited better mechanical properties thanothers. Under the same conditions, ternary additives could improve the properties andrefine microstructure of corundum abrasives more significantly than binary systems.The hightest single particle compressive strength of the abrasives aided withMgO-CuO-TiO₂was58.7N at the molar ratio of1.2:0.2:1, while that of the abrasivesaided with CuO-TiO₂-SiO₂was69.9N at the molar ratio of0.2:1.2:1. The phasetransformation temperature of alumina could be decreased effectively by introducingproper amount of CuO-TiO₂-SiO₂additives and the mechanical properties ofabrasives were enhanced at the same time. Compared with one-step sintering, theabrasives sintered through two-step method presented much finer grains andmicrostructure. Increasing the sintering temperature would obviously improve thesingle particle compressive strength of abrasives, but also induce the growth of grains.