整体叶盘电解加工组合式阴极结构优化及试验研究

Optimization and Experiment of Combined Cathode Structure in Electrochemical Machining of Blisk

在整体叶盘电解加工中,组合式阴极受狭窄加工区空间的限制,整体刚性难以提升。同时,组合式阴极结构特点使叶盆、叶背阴极刚性相互制约,若刚性分布不均,较弱一方会产生较大变形,影响加工精度和重复精度。为了在有限的刚性条件下均衡刚性分布,提出了一种阴极刚性优化方法,以叶盆、叶背阴极变形差为目标函数,通过有限元单向流固耦合分析法与黄金分割法获得了某组合式阴极的最优结构。采用优化结果开展了工艺试验,试验样件具有较好的加工重复精度。

In ECM blisk,because the structure of the combined cathode is limited by the narrow machining space ,it is difficult to improve its overall rigidity. Meanwhile ,the cathode rigidity in both suction surface and pressure surface rigidly restrict each other. And the non-uniformity distribution of the rigidity could lead to a large deformation in the cathode which would affect the machining and repeat accuracy. A method of optimization in cathode structure was proposed to balance the distribution of the rigidity. The deformation difference between suction surface cathode and pressure surface cathode was used as the objective function, and the minimum value was the optimal solution. The one- way coupling and golden section method were employed with finite element modeling （FEM） to obtain the optimal structure of cathode. And the experiments showed that the repeat accuracy was improved greatly with the optimal cathode.