Effects of wire feeding direction and location in multiple layer diode laser direct metal deposition

This study investigates the effect of wire feeding direction, angle and location in a high power diode laser (HPDL) direct metal deposition (DMD) process for single and multilayered clad/parts. A 1.5 kW diode laser was used to deposit single layer clad/track and build multilayer parts with different wire feeding conditions. These clad/parts were analysed using scanning electron microscopy (SEM), X-ray diffraction and optical microscopy. The best performance in terms of surface finish, geometry control and quality of sample was obtained by front feeding and placing the wire at the leading edge of the melt pool. By rear feeding, the best results were obtained by placing the wire at the trailing edge. The surface roughness increased by increasing the feeding angle for front feeding and decreased for rear feeding. The energy distribution, melt flow and rapid solidification processes were investigated.