Rapid microstructure modification of laser powder-bed fused superalloy IN718 using high-density pulsed electric current

Abstract

A novel high-density pulsed electric current (HDPEC) method is developed to modify the grain-scale microstructure of laser powder-bed fused Ni-based superalloy IN718, which has not been reported in other studies. Rapid micro-residual stress relief and micro-segregation alleviation were achieved without significant grain coarsening which is common in conventional heat treatment. This technique can be an alternative energy-saving post-treatment method for additively manufactured metallic materials, enabling rapid and efficient annealing and solution treatment.