Assessing crack susceptibility in blended copper-stainless steel compositions during laser directed energy deposition-based additive manufacturing

This study investigates the effect of composition and process parameters on the crack susceptibility of the Cu -SS304L system during laser directed energy deposition (LDED). The microstructure of LDED deposits is analysed aiming at elemental distribution and crack susceptibility. The trapping behaviour of Cu changes with Cu concentration. The crack susceptibility reduces with Cu concentration and escalates with an increase in laser power and scan speed, irrespective of composition. The mode of solidification cracking varied from the rupture of Cu film to crack-assisted porosity. Furthermore, the critical solidification cooling rate is estimated for LDED of different blended Cu -SS for crack-free deposition. The above findings offer insights into cracking behaviour and provide processing guidelines for LDED of Cu -SS.