Preparation,Properties And Micromorphology Of Microcrystalline Ceramic Corundum Abrasives

Compared with the traditional electric furnace corundum abrasive,the ceramic corundum abrasive produced by the sol-gel process is superior in strength,toughness,self-sharpness and service life.Which is widely used in modern industry due to its cost is much lower than the diamond,cubic boron nitride and other superhard abrasive.In this paper,the ceramic corundum abrasives were prepared by acidic sol-gel method.The precursor preparation process,additive types,additive ratio,addition amount and sintering system of ceramic corundum abrasives were explored.The mechanical properties of the abrasives were evaluated by the single-particle compressive strength,Vickers hardness and ball-milling toughness.Moreover,the microstructure of the abrasives was analyzed by SEM.In the system of BaO-B₂O₃,B₂O₃-TiO₂,BaO-TiO₂,the single particle compressive strength of the abrasive first shown an increase trend and then decreased,and achieved the maximum value of 39.4 N,39.9 N and 42 N at the molar ratio of3:10,10:7 and 9:7,respectively.Moreover,the microstructure of the abrasive sample was dense and the grains grown equiaxed.In the BaO-B₂O₃-TiO₂ ternary additive system,when sample sintered at 1400?for 90 min with 9:20:7 molar ratio of the BaO/B₂O₃/TiO₂ ternary additive system and4 wt%amount of the additive,the single particle compressive strength of the corundum abrasive had a maximum value of 50.2 N and a 0.96?m average size.The mechanical of the abrasive was comprehensive evaluated through testing the hardness,the compressive strength and the toughness.When sample sintered at 1400?for 90 min when the amount of additive was 4 wt%with BaO/B₂O₃/Cr₂O₃ molar ratio9:7:7,the sample possessed a dense microstructure and a 1.38?m average grain size.Moreover,the single particle compressive strength,the Vickers hardness and the ball milling toughness possessed the maximum value of 50.3 N?20.34 GPa and 97.9%,respectively When sintered at 1400?-1350?,the compressive strength,the Vickers hardness and the ball-milling toughness of the abrasives with BaO/B₂O₃/Cr₂O₃ ternary additives in the molar of 9:7:9 were increased to 61.22 N,22.40 GPa,and 98.7%,respectively,and the average grain size decreased to 1.09?m.