Use of 450-808 nm diode lasers for efficient energy absorption during powder bed fusion of Ti6Al4V

Abstract The additive manufacturing process selective laser melting (SLM) uses a powder bed fusion approach to fully melt layers of powdered metal and create 3D components. Current SLM systems are equipped with either single or multiple (up four) high-power galvo-scanning infrared fibre sources operating at fixed wavelength 1064 nm. At this wavelength, limited energy absorption takes place for most metals (e.g. alloys aluminium have less than 10% titanium 50-60% absorption). lower 1064-nm requires higher powers compensate the loss due reflectivity feedstock material. This makes use lasers within current inefficient. Further this, there is potential scale-up these an system architecture physical space requirements high economic cost, placing further limitations on state-of-the-art productivity. research investigates low power, highly scalable coupled diode influence shorter wavelengths (450–808 nm) material processing efficiency using area (DAM) approach. It was found that when Ti6Al4V, 11% 450-nm compared 808-nm 14% lasers. maximum temperature irradiation 450 nm 808 1920 0 C 1760 respectively only 3.5 W power. Due speed which DAM scans bed, pool cooling rate much slower (750–1400 C/s) traditional (10 5 –10 6 C/s). encouraged development β phases formed Ti6Al4V component. compact short viable source future systems, productivity methodology.