高速车铣加工三维颤振的稳定性分析与试验研究

针对立铣刀高速车铣加工,基于其切削原理采用解析法建立三维颤振稳定域的理论模型。在立铣刀四轴车铣加工模态试验基础上,仿真分析了颤振稳定域叶瓣图,结果表明立铣刀高速车铣加工产生颤振的条件与铣刀几何形状、工件材料、铣刀转速、切削深度和机床结构的频率响应函数等密切相关。在进行车铣切削颤振稳定域试验时,其切削力频谱分析的结果表明:当刀齿切入频率起主导作用时,切削过程是无颤振和稳定的;当系统模态频率起主导作用时,将产生颤振并测得切削力和表面粗糙度值都大于或高于无颤振情况。因此该理论模型及仿真结果对立铣刀车铣加工零件的加工效率和加工精度可提供相应的理论指导。

Stability analysis and experimental research for three-dimensional dither in processing of high speed milling

Aiming at high speed turn-milling by end mill,the theoretical model in stability range of three-dimensional dither was established on the basis of its cutting principle by using an analytic method. Based on modal test of 4-axial turn-milling by end mill,the leaf figure of the dither stability range was simulated and analyzed. The results show that: the geometrical shape of mill,material of work-piece,rotating speed of mill,cutting depth and the frequency response function of machine-tool’s structure are closely related to the conditions that can produce dither in high speed turn-milling by end mill. In the test of stability range of dither in turn-milling,the results of spectrum analysis for cutting force show that: cutting is stable and non-dither when cutting-in frequency of cutter tooth plays the leading role in force spectrum. Dither is produced when modal frequency of the system plays the leading role in force spectrum. The measured value of cutting force and surface roughness are also higher than those in the condition of non-dither. Thus the theoretical model and results of simulation can provide theoretical guidance for processing efficiency and surface quality of work-piece manufactured by end mills.