Effects of ZrO2 and Y2O3 on physical and mechanical properties of ceramic bond and ceramic CBN composites

In order to optimize the structure performances of ceramic cubic boron nitride (CBN) grinding wheels, the effects of ZrO2 and Y2O3 addition on the physical and mechanical properties of ceramic bond and ceramic CBN composites were systematically investigated. The basic ceramic bond was composed of B2O3, Al2O3, SiO2, Li2O and Na2O. The additions of ZrO2 and Y2O3 had a certain effect on refractoriness, liquidity, flexural strength of ceramic bonds. The experimental results demonstrated that in the ceramic bonds, both ZrO2 and Y2O3 could promote the formation of glass grid, while the ceramic bond strength would further increase. In addition, the new phase of YBO3 appeared in the ceramic bond, due to the filling of Y2O3. When the contents of ZrO2 and Y2O3 were 4 wt% respectively, the strength of the ceramic bond was highest, increasing by 23% (16.1 Mpa) compared to the basic ceramic bond. The last point required to be pointed out was that the phase transformation toughening of ZrO2 cannot be achieved and it was limited by low temperature sintering.