Recast Layer Thickness Characterization of Array of Micro Features Using X-Ray Micro Computed Tomography

Abstract

Destructive characterization of recast layer on reverse micro EDM-ed (RMEDM) surface renders the component unusable for its intended application. X-ray micro computed tomography (µCT) is a non-destructive technique widely used for characterization of internal structures of different materials. Array of hemispherical shaped micro features fabricated by RMEDM by employing taper ended blind holes led to variation in recast layer thickness of the micro features both along its length and position on the surface of workpiece. µCT characterization of recast layer thickness revealed that with respect to location on micro feature, the tip of micro feature had the highest recast layer thickness and the base the lowest. Also, with respect to location of micro feature on the surface of workpiece, the micro feature at the periphery had the lowest recast layer thickness whereas the micro feature at the centre had the highest.