Anode characteristics and electrochemical machining of U71Mn alloy in different electrolyte solutions

Electrochemical machining (ECM) is one of the most ideal machining methods for difficult-to-cut material of U71Mn alloy. Therefore, it is vital to obtain the electrochemical characteristics of the material. In this paper, these characteristics are measured with an electrochemical station, and a series of experiments are conducted to verify them. The electrolyte solutions of 15 wt.% NaNO 3 and 15 wt.% NaCl are selected for the experiments. The polarization experimental results indicate a broader range of passive regions in the NaNO 3 electrolyte solution compared with that in the NaCl. This means that a higher voltage is required to break down the passive film in ECM experiments. Meanwhile, the current efficiency of the alloy is measured in 15 wt.% NaNO 3 and 15 wt.% NaCl. The results indicate that the current efficiency of U71Mn alloy in NaCl electrolyte solution is higher than that in NaNO 3 electrolyte solution. The electrochemical characteristics of U71Mn alloy are verified with a series of single-factor experiments, and reasonable machining parameters are obtained. The suitable range of machining voltage is 10 to 20 V, and the range of inter-electrode gap is 0.1 to 0.2 mm in these two electrolyte solutions. Finally, multi-parameter experiments are carried out in these two electrolyte solutions to obtain machining samples. The experimental results show that 15 wt.% NaNO 3 proved to be a better electrolyte solution for U71Mn alloy, the surface roughness (SR) of the workpiece is Sa 0.72 μm, and the material removal rate (MRR) is 0.096 g/min.