Comparative Evaluation of Surface Integrity of CMSX-4 Nickel-Based Superalloy After Grinding, Wire Electrical Discharge Machining, and Electrochemical Machining Processes

Abstract

CMSX-4 nickel base superalloy is the second-generation alloy of this single crystal, which has improved its mechanical properties due to the lack of grain boundaries. According to the working conditions in using this superalloy, achieving less surface defects and lower surface roughness after the manufacturing process is very important. Therefore, the comparison of the surface of this superalloy after grinding, wire electro discharge machining (WEDM) and electrochemical machining (ECM) has been investigated by scanning electron microscope (SEM) and surface roughness. Surface roughness after WEDM, ECM and grinding are 3.337, 0.549, and 0.458 micro-meter, respectively. ECM and grinding processes are suitable from the point of view of surface roughness. On the other hand, in the SEM images after ECM, the defects caused by this process were not observed (compared to the other two processes). Besides, hardness after WEDM, ECM and grinding are 38.9, 39.7 and 40.1 HRC respectively. To conclude, the ECM process has desirable results and is a suitable alternative process for manufacturing parts with smooth surface and less surface defects. © ASM International 2023.