基于数值积分方法的铣削稳定性预测研究

Research on Milling Stability Prediction Based on Numerical Integration Method

针对立式加工中心铣削颤振现象,用数值积分方法预测铣削加工过程中的稳定性。首先用时滞微分方程表示受颤振影响的单、双自由度铣削动力学模型,对时滞周期进行离散;然后用数值积分方法求解时滞微分方程,依据Floquet判定铣削加工稳定性,获得稳定性叶瓣图;最后为验证数值积分方法求解的正确性,进行参数识别试验获取铣削力系数和模态参数,从求解得到的叶瓣图中选取加工参数进行试验验证。数值仿真结果表明,数值积分方法的计算效率和计算精度优于1st-SDM方法和1st-FDM方法。试验结果表明,数值积分方法的求解结果与试验结果相符,可以指导铣削工艺参数的选取,确保铣削加工稳定。

In this paper,the stability of milling in vertical machining center is predicted by numerical integration method.Firstly,the single-degree-of-freedom and two-degree-of-freedom milling dynamic models affected by chatter are represented by time-delay differential equation,and the delay period is discretized;Secondly,the time-delay differential equation is solved by numerical integral method,the milling stability is determined according to Floquet,and the stability lobe diagram is obtained.Finally,in order to verify the correctness of the numerical integration method,the milling force coefficient and modal parameters are obtained by parameter identification experiments,the machining parameters are selected from the obtained lobe diagram for experimental verification.The numerical simulation results show that the numerical integration method is superior to the 1st-SDM method and the 1st-FDM method in terms of computational efficiency and accuracy.The numerical integration method solution results are consistent with the experimental results,which can guide the selection of milling process parameters and ensure the stability of milling processing.