Simulation study on cathode structure optimization of aluminum alloy thin-walled internal spiral deep hole electrochemical machining.

In order to solve the problems of easily distorted and poor surface quality in machining aluminum alloy thin-walled internal spiral deep hole parts, a precision-forming electrochemical machining (ECM) method was proposed. In this paper, the physical model of the pull-type downstream and pull-type countercurrent cathode was established, and the simulation study on the flow field of two kinds of cathode gap was carried out. The inclination angle of the cathode liquid supply hole was optimized. The simulation results showed that the flow rate of the pull-type downstream cathode electrolyte is 21% higher than the pull-type countercurrent cathode, and the flow field is more uniform when the inclination angle of the cathode liquid supply hole is 30°. Using the self-developed large-scale horizontal electrochemical machining equipment, under the conditions of voltage 7.5 V, current 1850 A, composite electrolyte 10%NaCl + 9%NaNO3, electrolyte temperature 30 °C, inlet pressure 1.2 MPa, and cathode feed rate 100 mm/min, the surface roughness of Ra0.741 μm and the forming accuracy of 0.035 mm aluminum alloy thin-walled inner spiral deep hole stable machining was completed. The research shows that the cathode structure optimization simulation can effectively shorten the cathode development cycle and reduce the test cost. [ABSTRACT FROM AUTHOR]