大切深数控电解铣削加工阴极设计及试验研究

难加工材料整体叶轮广泛应用于航空领域,采用传统切削加工存在刀具磨损快、加工效率低等问题。本文针对某型号复杂整体叶轮,提出大切深五轴数控电解铣削预加工方法。通过设计锥形螺旋刃阴极,分析不同旋转角下单、双螺旋刃出口流场分布,得到旋转角720°的单螺旋刃阴极出口压力和流速分布均匀。同时开展大切深数控电解铣削加工试验,结果表明:在选取的工艺参数范围内,加工平衡间隙和进给速度随着加工电压升高而增大;较低的电解液温度有利于实现小间隙加工,可显著提高加工精度;主轴转速达到1 500 r/min后对加工速度影响较小。得到大切深数控电解铣削整体叶轮加工叶片,一次最大切深可达65 mm,余量误差控制在0.5 mm范围之内,提高了整体叶轮加工效率。

Cathode Design and Experimental Study of Large Cutting Depth NC Electrochemical Milling

The integral impeller made of difficult to machine materials is widely used in the aviation field. The traditional machining has the problems of fast tool wear and low machining efficiency. In this paper, a large cutting depth five axis numerical control electrochemical milling pre-processing method is proposed for a certain type of complex integral impeller. Through the design of the conical spiral blade cathode, the flow field distribution at the outlet of single and double spiral blades with different rotation angles is analyzed, and the distribution of the pressure and flow velocity at the outlet of the single spiral blade cathode with rotation angle of 720° is uniform. At the same time, the experiment of NC electrochemical milling with large cutting depth is carried out. The results show that: Within the range of selected process parameters, the machining balance gap and feed speed increase with the increase of machining voltage; The lower electrolyte temperature is conducive to the realization of small gap machining, which can significantly improve the machining accuracy; The spindle speed reaches 1 500 r/min, which has little impact on the machining speed. The results show that the maximum cutting depth can reach 65 mm, and the margin error can be controlled within 0.5 mm, which improves the machining efficiency of the whole impeller.