Jet electrolytic plasma polishing process for high temperature alloy additive manufacturing of large size surfaces

Aiming at the problem of surface finishing of large-size additively manufactured high-temperature alloy parts, a jet electrolytic plasma polishing process for the surface treatment of specific large-size high-temperature alloy samples has been developed. Taking the typical high-temperature alloy curved workpiece as the research object, through the orthogonal test research results, this research has studied the influence law of different process parameters on the surface roughness of the alloy and realized the verification of the process effect of the surface roughness of the high-temperature alloy surface polished by jet electrolytic plasma polishing. It was found that the degree of influence of the four process parameters on the surface roughness was in the following order: flow rate > cathode and anode spacing ≈ voltage > temperature. The process conditions adapted to the surface polishing of high-temperature alloys are as follows: a cathode and anode spacing of 25 mm, a voltage of 340 V, an electrolyte temperature of 70 °C, and an electrolyte flow rate of 1.2 l/h. The surface roughness of the workpiece obtained after polishing under these process conditions is the lowest, and the surface roughness (Ra) of high-temperature alloys decreases from 13.251 to 0.853 μm, with a decrease rate of 93.56%. The experimental results show that the impurity elements on the surface of the high-temperature alloy have been removed by electrolytic plasma polishing, the residue of electrolyte component elements is not detected, and the specimens treated by electrolyte plasma polishing present a better corrosion resistance.