Electropolishing and electropolishing-related allowances for IN625 alloy components fabricated by laser powder-bed fusion

This study focuses on the optimization of the applied potential and cycling time for the efficient electropolishing of IN625 test coupons containing multiple surfaces, which are oriented with respect to the building platform of a commercial laser powder-bed fusion system under angles varying from 0A degrees to 135A degrees. It is shown that despite a large scatter in the as-built surface finish, ranging from Ra = 1.8 mu m (0A degrees) to Ra = 18.6 mu m (135A degrees), it is possible to polish down all the differently oriented surfaces to a uniform roughness of Ra = 1.5-3.5 mu m. Furthermore, the measurement of the thickness evolutions during electropolishing of the differently oriented test coupons allows us to establish the build orientation-dependent allowances for the finishing of IN625 components fabricated by laser powder-bed fusion.