基于应力集中理论的磨削力模型

Model of Grinding Force Based on Stress Concentration Theory

将应力集中理论引入磨削过程研究,分析了磨削过程中的应力集中现象,建立了基于应力集中的单颗磨粒磨削力模型,应用该模型分析了磨削力随磨粒磨损面积率的变化机理,并分别建立了单颗磨粒磨削法向力、切向力随磨粒磨损面积率变化的解析式,由解析式可知磨削法向力、切向力都与磨粒磨损面积率呈二次函数关系,得出了磨削后工件材料的累积残切厚度增大是磨削法向力增大的重要原因。在此基础上,结合实际生产中使用的砂轮特点,推导出了适用于实际磨削过程的基于应力集中的多颗磨粒砂轮磨削力随磨粒磨损面积率变化的解析式,用所建模型计算的结果与试验数据吻合较好。

Stress concentration theory was introduced into study of grinding, and the stress concentration phenomenon in grinding process was analyzed. A single-grit model of grinding force was established based on stress concentration theory. The influence mechanism of grit-wear-area rate on cutting force was clarified with the model. Functions between grinding force and grit-wear-area rate was established. The functions showed the quadratic function relationship between grinding force and grit-wear-area rate, and the increase of the cumulative residual-grinding-thickness results in the rapid increase of normal grinding force. Furthermore, by taking the feature of the grinding wheel in use into consideration, functions of grinding force for multi-grit grinding wheel was established. The validity of the model was verified by the experimental data.