磨料表面微氧化对cBN磨具磨削性能的影响
Effect of the cBN Grit Surface Oxidation on Grinding Performance of the Vitrified cBN Tool

为了解决陶瓷结合剂cBN磨具在高速磨削的过程中易发生断裂以至于失效的问题,提高cBN磨具材料的磨削性能,采用微氧化技术对cBN磨粒进行了表面处理,研究了cBN磨粒表面微氧化对cBN磨具中磨粒与结合剂间界面结合方式、界面结合力、磨具强度以及磨具磨削磨损的影响规律,并分析了磨具磨削磨损失效机制。结果表明:表面微氧化后的cBN磨粒表面氧化膜的成分是B2O3;因B2O3与结合剂组分发生反应致使结合面两侧产生元素互扩散,使得陶瓷结合剂与cBN磨粒界面间的机械结合方式转为化学结合方式;与cBN磨粒未经过氧化的磨具相比,经过表面氧化的cBN磨粒制备的磨具中陶瓷结合剂与cBN磨粒结合面剪切力提高了2？？5倍,磨具抗弯强度提高了18％,且磨削磨损性能提高了2？？6倍;cBN磨粒与结合剂结合力的提高可以使磨具强度提高,磨具磨削磨损时随着磨削力增大磨粒不易脱落,并逐渐发生自锐,从而降低磨具的损耗,提高磨削效率。
The surfaces of cBN abrasive particles are treated by micro？？oxidation to solve the ceramic bond cBN grinding tool fracture failure problem that occurs during high？？speed grinding and to improve the grinding performance of the cBN grinding tool material. The influence of cBN abrasive particles surface micro？？oxidation to the interfacial bonding method, the interfacial bonding strength, the cBN tool strength and the cBN tool grinding performance are studied. And the wear failure mechanism of the cBN tool is analyzed. The results show that the oxide film component on cBN abrasive particle surface is B2O3. Element mutual diffusion at the interface occurs through the react between B2O3 and binder components, and the interface bonding between vitrified bonds and cBN abrasive is transformed from mechanical bond to chemical bond. Comparisons with the grinding tool without abrasive particle oxidation show that the interface shear stress of the grinding tool with abrasive particle oxidation increases 2？？5 times while the bending strength has a 18％ increase and the grinding wear resistance improves 2？？6 times. The improvement of the combination between cBN abrasive particle and binding agent could make abrasive self？？sharpening happen rather than shedding when grinding force increases. In that way, the loss of grinding tools decreases while the grinding efficiency increases