Die-sinking and rotary EDM surface and subsurface analysis of MoSi2-SiC ceramic composites

Rotating EDM and die sinking EDM were used to compare the machinability of MoSi2-SiC composites. Surface flaws such as micro cracks, un melted spherical particles, pores, a recast layer and craters following EDM can be attributed to the high hardness and poor toughness of the MoSi2-SiC. Die sinking EDM and rotary EDM, as shown by a comparison of recast layer thicknesses, produce the most uniformly thin white layers, at 92 and 30 µm respectively. The study found that the area fraction yield for porosity ranged from 8.18% to 12.922% when using rotary EDM, but only from 2.33% to 8.10% when using die-sinking EDM. According to the EDAX, the spongy exterior of a composite is the result of a lot of gas being produced. Although the rotational movement of the tool sweeps the resolidified particles away, Rotary EDM resulted in a thinner and less uniform recast layer while still producing good surfaces.