单向碳纤维复合材料直角自由切削力的研究

Study on Cutting Forces of Unidirectional Carbon Fiber Reinforced Plastics under Orthogonal Cutting

以单向碳纤维复合材料(UCFRP)直角自由切削为研究对象,给出了纤维方向角0°-90°范围内的水平和垂直两方向切削力的理论计算方法。基于切削实验观察,发现在小切削厚度下,刀具刃口半径的作用应当考虑到切削力的计算中去。将切削区分为3个变形区分别计算切削力,总的切削力即为此3个变形区切削力之代数和。计算方法中考虑了刀具前角、刀具刃口半径、切削厚度、材料力学性能等多方面实际因素,发现纤维方向角、刀具前角、切削厚度等因素均对切削力的变化有较明显的影响。经计算值与实验数据对比,发现两者间有较好的一致性。

A mechanics model for predicting the orthogonal cutting forces of unidirectional carbon fiber reinforced plastics （UCFRP） with fiber orientation varying from 0°～to 90° is developed. Based on the experimental inspection and understanding, the model divides the cutting zone into three characteristic regions, i. e. , chipping, pressing and bouncing regions. The cutting tool geometry, such as rake angle and nose radius, and other parameters, such as depth of cut and mechanical properties of the workpiece materials, are also considered in the modeling. A systematic comparison of the model predictions of cutting forces with experimental measurements show that the mechanics model developed captures very well the mechanism of cutting unidirectional carbon fiber reinforced plastics.