Improved Compact 1 kW Diode Laser Module Emitting at 780 nm for the Efficient Direct Additive Manufacturing of Aluminium

Additive manufacturing (AM) of aluminium has become increasingly important, for example in mobility applications such as fabrication of ultra-low-weight vehicle bodies in the transport sector [1]. The use of a direct diode laser module emitting at wavelength $\lambda=780$ nm has many advantages over established $\lambda=10\text{xx}$ nm fibre-or YAG-laser systems. First: a higher process efficiency due to the more than doubled absorption of aluminium at $\lambda=780$ nm. Second: a higher light generation efficiency by eliminating the pump step. And third: a higher process flexibility since light is generated directly at the process head and no high-power delivery fibre is needed.