【摘要】 航空发动机压气机钛合金叶片是一种典型的曲面薄壁结构件，在材料和结构上具有双重难加工特性，铣削加工过程中极易发生颤振，难以保证加工质量。为实现该类零件的高质量、高稳定性加工，提出将NSGA-Ⅱ算法与叶片稳定性分析相结合，从而实现对叶片加工工艺参数优化的方法。首先，基于正交试验建立多目标优化模型，通过NSGA-Ⅱ算法初选工艺参数。在此基础上，进行模态试验以获取叶片精加工前的模态参数，进而利用半离散法绘制稳定性叶瓣图来预测叶片在不同工艺参数下铣削加工过程中的稳定性，并优选叶片精加工工艺参数，最后通过实验验证该方法具有可行性。更多还原

【Abstract】 Objectives: As a typical thin-walled curved structural component, the titanium alloy blades used in aeroengine compressors present dual challenges of difficult-to-machine material and low structural rigidity, making them prone to chatter during milling, which significantly impairs machining efficiency and surface quality. To achieve efficient and high-quality machining of such parts, this study aims to develop a method for optimizing milling parameters by integrating multi-objective optimization with dynamic stability analysis, thereby suppressing milling chatter, improving machining efficiency, and ensuring machining quality. Methods: Firstly, orthogonal experiments are designed and carried out. Based on the experimental data, a multi-objective optimization model is constructed with spindle speed, feed per tooth, depth of cut, and width of cut as variables, and with material removal rate, surface roughness, and cutting force as optimization objectives. Secondly, the NSGA-Ⅱ algorithm is employed to perform global optimization of the multi-objective model, yielding an initial Pareto-optimal set of process parameters. Thirdly, modal tests are conducted on the blade before finish machining to obtain its dynamic parameters such as natural frequency and damping ratio. Combining the milling force model with the modal parameters, a semi-discrete time-domain method is applied to analyze the blade-tool system dynamics, and stability lobe diagrams are plotted to predict stable cutting regions under different parameter combinations. Finally, by integrating optimization objectives and stability constraints, parameters that satisfy both high efficiency and quality requirements while avoiding chatter risks are selected from the Pareto set. Results: Comparative experiments are conducted to verify multiple sets of process parameters, and the results are consistent with predictions. The results show that using the optimized parameter set 1#(spindle speed 6 137 r·min^-1, feed rate 245 mm·min^-1, depth of cut 0. 10 mm, width of cut 0. 10 mm) results in a blade surface roughness below 0. 24 ??m, excellent surface quality, blade profile deviations within ±0. 01 mm, minimal deformation, fully meeting process specifications. In contrast, using parameter set 2#(spindle speed 6 051 r·min^-1, feed rate 315 mm·min^-1, depth of cut 0. 38 mm, width of cut 0. 12 mm) leads to surface roughness values of 0. 594 ??m on the pressure side and 0. 788 ??m on the suction side, with some profile deviations exceeding ±0. 01 mm. Using parameter set 3#(spindle speed 6 121 r·min^-1, feed rate 342 mm·min^-1, depth of cut 0. 21 mm, width of cut 0. 20 mm) results in surface roughness of 1. 539 ??m on the pressure side and 0. 839 ??m on the suction side, with profile deviations also beyond the ±0. 01 mm range. These results further demonstrate that the proposed method effectively identifies and avoids chatter-prone regions, achieving a balanced optimization of quality, efficiency, and stability in process parameters. Conclusions: The process parameter optimization method proposed in this study, which integrates NSGA-Ⅱ with stability lobe diagram analysis, enables efficient and high-quality machining of aero-engine titanium alloy blades. This approach not only allows initial selection of high-performance process parameters amid multi-objective conflicts but also further refines the parameters by incorporating dynamic machining characteristics to ensure stable cutting, thereby effectively suppressing chatter and improving both machining efficiency and surface quality. Moreover, this research provides a quantifiable and predictable optimization pathway for the process planning of thin-walled curved components such as blades, and offers theoretical and technical support and practical guidance for the high-performance manufacturing of key aero-engine key components.更多还原