平面曲线端铣加工过程铣削力的建模与预测

针对平面曲线端铣加工过程，提出一种考虑瞬时进给方向的铣削力预测方法。铣削加工时每齿进给量、切入/切出角以及瞬时切屑厚度等铣削参量随着曲线曲率的改变而变化，将单个频齿周期内的曲线加工过程看做是一系列铣削条件恒定的微小稳态加工过程，建立了等效进给量、切入/切出角的矢量计算模型，通过计算每一微小阶段的铣削参量，推导了平面曲线端铣中基于傅里叶级数展开的铣削力模型。以PCrNi3MoVA钢为工件材料，分别进行圆弧和Bezier曲线端铣加工试验，试验结果表明，预测的铣削力在幅值和变化趋势上与试验测量结果吻合良好，验证了该铣削力预测方法的有效性。

Modeling and Prediction of Cutting Forces in End Milling of Curved Surfaces

A novel mechanistic cutting force model is presented for end milling of curved surfaces, including the effect of instantaneous feed direction. In machining of curved geometries where the curvature varies continuously along tool path, the cutting parameters, such as feed per tooth, entry/exit angle, and instantaneous undeformed chip thickness, vary along tool path. The cutting process of curved surface is discretized into a series of steady-state cutting processes at intervals of feed per tooth, and a vector model for these parameters of each segmented cutting process is presented. The Fourier series expansion is used for deriving the cutting force model. Combined with the milling force coefficients fitted by a series of slot milling tests, the predicted cutting forces in machining PCrNi3MoVA workpiece with circular and Bezier curve geometries are achieved, respectively. The prediction accuracy of the model is validated experimentally and the predicted and measured results correspond well with each other.