Prediction of stability limit for multi-regenerative chatter in high performance milling

Abstract

Chatter is one of the most important factors that inhibit the improvement of productivity and deteriorate the machined surface quality in milling process. In order to obtain good surface quality, classical machining process usually has to take conservative milling parameters. Based on the authors' previous work, this paper presented a new thirdorder discretization method to compute the stability lobes considering multi-regenerative chatter effect. A mathematical model, which is suitable for the dynamic system with non-uniform pitch cutter or cutter run-out, is first established for multi-regenerative chatter. Then, three examples are performed to test the validity of the proposed method. The first example is for the case that the system takes a non-uniform pitch cutter. In the second example, after the modal parameters, run-out parameters and cutting force parameters are gained from experiments, the stability lobes are predicted using the proposed method and subsequently testified by a series of experiments. The third example is for the case of existing cutter run-out. The final computation and experiment results indicate the effectiveness and validity of the proposed method. It is applicable in high performance machining for achieving a good parameter combination.

Determination of the stability lobes with multi-delays considering cutter’s helix angle effect for machining process

“…Zaghbani et al 41 use the stability technology on a robotic machining system. In our previous works, 42,43 a high order full-discretization method is proposed to predict stability lobes with high accuracy. Huang et al 44 present a liner approximation of acceleration method for stability lobes prediction.…”

“…The chatter induced by multi-regenerative effect is also studied and analyzed. The literatures 38,42,43 have introduced the cutter runout’s effect on the milling systems. And researchers find that the cutter runout not only affects the actual pitch angles but also affects the actual cutting depths.…”

“…This is proved using our method in previous works. 43 Using some special cutters with non-uniform distribution of cutter edges, the chatter with multi-regenerative effect can be depressed more easily in machining process compared with the process machined using the cutter with uniform distribution of cutter edges. Altintas and Budak 22 find this phenomenon and then give an classical example which has been proved utilizing experiments.…”

Integrated measurement and machining technology of complex surfaces

“…相关研究以高速加 工切削热的产生和变化规律及检测技术的研究居多, 旨在为高速加工切削参数优化、 控制或切屑去除机理 分析等提供依据 [33] . 美国学者克莱姆森大学Henderson 等人 [34] [36] 、半离散法 [37] 和全离散法 [38] 等加工稳定 性极限值的数值解法, 并已考虑了刀具跳动等因素 的影响 [39] , 特别是在高速加工和难加工材料零件高 表面完整性加工要求的推动下, 切削颤振的在线识 别、 预测及抑制的方法与策略成为研究的热点和难点 之一 [40] . 切削加工中的振动能够通过位移计、加速度 计、测力计、声信号和光学检测装置等检测出来.…”

Location-Dependent Prediction of Dynamic Stability Limit for Peripheral Milling of Surfaces with Variable Curvatures

“…Insperger presents a semidiscretization method in time domain, which, by discretizing the delay term, converts the delay differential equations governing the milling dynamics into a set of ordinary differential equations; this allows the construction of a system state transition matrix, based on which the stability of the system can be assessed using Floquet's theory [4]; moreover, Zatarain employs this method to analyze the impact of milling cutter's helix angle on the stability boundary by means of this method [5], and Long examines the effect of speed variation on the chatter stability [6]. Guo studies the milling stability limit associated with the multiregenerative effects based on the 3rd-order semidiscretization method [7]. Ding proposes a full-discretization method, which, by fully discretizing the delay and state terms, allows the application of Floquet's theory to determine the stability limit of the system [8].…”