Multiple 450 nm diode laser processing of TI64 powder

Diode Area Melting (DAM) presents an alternative approach to traditional Laser Powder Bed Fusion (PBF-LB/M) approaches, integrating multiple individually addressable low-power fibre-coupled diode lasers into a laser head; these traverse across a powder bed to melt powdered feedstock. DAM research to date has focused on using low-power 808 nm lasers to process Ti6Al-4V (Ti64) powder. This work focuses on using multiple short wavelengths 450 nm 4W lasers to process Ti64 feedstock. Previous studies found that when processing Ti64, absorption was 11% higher using 450 nm lasers when compared to using 808 nm lasers and 14% higher than 1064nm laser. This work demonstrated the potential to use shorter wavelength lasers in DAM/LPBF for improved melting efficiency. Also, it aimed to examine the impact of 450 nm diode lasers on Ti64 and generate a parameter map for this material. It was found that low power (4W) multiple 450 nm diode lasers can successfully melt the Ti64 for AM applications with above 95% density.