Effect of CuO–TiO2–SiO2 additions on the sintering behavior and mechanical properties of corundum abrasive synthesized through sol–gel method

The effect of ternary compound additives, CuO–TiO2–SiO2 on the phase transformation, densification and microstructure of corundum abrasive were investigated. The results showed that the co-doping had synergistic effects on reducing the phase transformation temperature from γ- to α-Al2O3, enhancing the densification and refining the microstructure of corundum abrasive particles. With the addition of CuO, TiO2 and SiO2 fixed at 3 wt% of the total weight of abrasive and in the molar ratio of 7:7:5, the samples sintered at 1400 °C for 0.5 h reached about 99.3% of theoretical density. The abrasives exhibited a homogeneous microstructure and excellent mechanical properties with single particle compressive strength higher than 40 N in all doped samples. The influence of each additive and their combined effects on the sintering of abrasives were also discussed in detail.