球头铣刀动态铣削力数值仿真

摘要

To predict milling force of ball-end milling cutter when milling complex surface,the cutting edge of the cutter is divided into discrete micros and oblique cutting model is established.Taking influences of hardening,strain rate and temperature into account in the equivalent plane,Oxley orthogonal cutting model in plane is used to oblique cutting mode.The flow stress and discrete micro cutting forces are calculated by the model.The involvement of each interval instantaneous cutting edge is determined based on cutter-workpiece contact zone.A numerical model of milling force in any feed direction and any surface curvature is established.Three-dimensional Metal cutting is simulated on finite element analysis software Ansys/LS-Dyna under the same conditions.Effectiveness of numerical model is verified by comparing two results.In addition,computing time and storage space required are much less than the FEA.The numerical model can be also used to other reference of metalworking such as milling,turning and drill%为了优化设计球头铣刀铣削复杂曲面的铣削力,将切削刃离散为切削微元,建立斜角切削模型.在等效平面内综合虑加工硬化、应变率及温度的影响,将二维正交切削Oxley模型沿用到斜角模型中计算流动应力及微元切削力.利用铣削刀具-工件接触区域确定刀刃微元切削状态,建立任意进给方向及曲面曲率的铣削力数值模型.运用Ansys-Dyn软件进行金属三维切削仿真分析,经结果对比验证,提出铣削力数值模型的有效性,且计算时间和所需存储空间远远小于有限元分析.证明改进数值模型可作为立铣,车削及钻削等其它金属加工方式的优化设计参考.