As one of the vital technological factors influencing the machining quality, machine tool fixture has been regarded as an important research object by scholars at home and abroad. In this paper, a new method for rapid evaluation of clamping scheme was presented based on the study of machining deformation of aerospace complex thin-walled parts. Firstly, Through the modal analysis of the thin-walled parts, the weak links of the structure and the direction of the large vibration displacement of the nodes are found. Then, the maximum displacement and natural frequency of the main vibration direction under different clamping schemes were obtained after intercepting several nodes and analyzing through FE software. The optimal clamping scheme was obtained through the result comparison. Finally, based on the existing research results, a mathematical model of evaluating the complexity of fixture characteristics was constructed. In this model, the stiffness values of multiple joints were considered, and the characteristic machining stiffness and the average value ∆K were obtained so as to evaluate the deformation resistance of the thin-walled parts. The influence of different clamping schemes on machining quality was quantitatively evaluated by the index. On the basis of the proposed method, a case study of aerospace thin-walled parts was conducted, and then the rapid evaluation and optimization of the milling clamping scheme for thin-walled parts were realized.

作为影响加工质量的重要技术因素之一，机床夹具已被国内外学者视为重要的研究对象。在研究航空航天复杂薄壁零件加工变形的基础上，提出了一种快速评估装夹方案的新方法。首先，通过对薄壁部件的模态分析，发现了结构的薄弱环节以及节点大振动位移的方向。然后，通过截取多个节点并通过有限元软件进行分析，得到了不同夹紧方式下主振动方向的最大位移和固有频率。通过比较结果获得最佳的钳位方案。最后，根据现有研究结果，建立了评估灯具特性复杂度的数学模型。在该模型中，考虑了多个接头的刚度值，以及特征加工刚度和平均值Δ获得K以便评估薄壁部件的抗变形性。通过该指标定量评估了不同夹紧方式对加工质量的影响。在此方法的基础上，以航空航天薄壁零件为例，实现了薄壁零件铣削夹紧方案的快速评估和优化。