Comparative Study of FeCl3 and CuCl2 on Geometrical Features Using Photochemical Machining of Monel 400

In this study, Monel 400 was machined using etchants, like ferric chloride (FeCl3) and cupric chloride (CuCl2) at different temperatures, concentration and type of geometry (viz. circular, hexagonal, square, rectangular and triangular). The study focuses on the comparative impact of input process parameters in perspective of depth of etch, undercut, and weight loss. Comparative study of FeCl3 and CuCl2 determines that the overall performance is better for ferric chloride etchant. The undercut observed in FeCl3 was more than CuCl2, but the better geometrical accuracy found with CuCl2 etchant solution. Type of geometries responsible for the depth of etch and weight loss. Triangular geometry shows higher weight loss and depth of etch. Higher weight loss and depth of etch is observed with FeCl3 than CuCl2 etchant. The weight loss and depth of etch increases from 0.0504 g to 0.0737 g and 0.0436 μm to 0.1547 μm respectively for FeCl3 for circular, hexagonal, square, rectangular and triangular shapes. Similarly, for CuCl2 these values are 0.0386 g to 0.0686 g and 0.0236 μm to 0.117 μm respectively.