Research On The Preparation And Properties Of Low Temperature Vitrified Bond For New Ceramic Alumina Abrasive Tool

Following the development of super-precision grinding, super-speed grinding,high-productivity grinding and difficult-machining material grinding, traditionalcorundum and SiC abrasive materials can no more satisfy the requirements of modernproduction. Owning to the perfect abrasiveness and the high cost performance, newceramic alumina abrasive tools show extensive development and application prospects.In this research, the preparation and properties of low temperature vitrified bond fornew ceramic alumina abrasive tool was investigated. Traditional ceramic bond andglass-ceramic bond were prepared for the ceramic alumina abrasive tools. The effectof constitute of the vitrified bond and the sintering schedule on the vitrified bond andthe ceramic alumina abrasive tools were discussed. The results were shown asfollows:（1） Clay-feldspar-borosilicate glass basic system traditional ceramic bondFollowing the increase of Al/Si, the refractoriness of the vitrified bond markedlyincreased. When the content of borosilicate glass was58.17%wt, thecorrosion-resisting property was best. However, when it was further increasing, thecorrosion-resisting property deteriorated.When cryolite was introduced into the basic vitrified bond, the refractoriness ofthe vitrified bond decreased rapidly. The fluidity of the vitrified bond increased at firstand then declined with the increasing of the content of cryolite. When the cryolitecontent was15%wt and the sintering temperature was930℃, the bending strength ofthe abrasive tool researched the highest value of55.19MPa, moreover, thecorrosion-resisting property of the referring abrasive tool was excellent.The refractoriness and the fluidity of the vitrified bond increased slightly withthe introducing of MgO into the basic vitrified bond. When the MgO content was2%wt, the bending strength of the abrasive tool researched the highest value.Moreover, the introducing of MgO into the basic vitrified bond would improve thecorrosion-resisting property.（2） Al₂O₃-SiO₂-B₂O₃-R2O-MgO-F basic system glass-ceramic bondDoping7.17%wt Na3AlF6and3%wt CeO₂into the basic vitrified bond wasconducive to reduce the refractoriness, Tg and Tp, and was also capable to enhancethe level of crystallization. Similarly, the sintered glass-ceramic bond presents ahigher fluidity, wettability, and mechanical strength. Meanwhile, the coefficient of thermal expansion of the sintered glass-ceramic bond is better matched to that of theceramic alumina abrasives. Furthermore, compared with CaF2, Na3AlF6is a very goodlow-melt phase and nucleating agent in this basic system. The quantity of Fe₂O₃added to the glass should be controlled within a certain range for the sake ofincreasing the precipitation of mica crystals.The ceramic alumina abrasive tool, using modified glass-ceramic bond whichwas introduced7.17%wt Na3AlF6and3%wt CeO₂into the basic vitrified bond, alsopossessed the highest value of the bending strength. The microstructure was dense andfew pores got exposed. Meanwhile, the interfacial bonding state of it was excellentand the abrasive grits combined tightly by the bonding bridge. In addition, thecorrosion-resisting property was better than other samples.