Micro Laser Melting: Analyses of Current Potentials and Restrictions for the Additive Manufacturing of Micro Structures

Although there is a significant requirement for complex micro parts, current metal processing additive manufacturing techniques are limited in achievable part accuracy and geometric resolution. Due to the recently developed process of Micro Laser Melting (MLM) new potentials in micro manufacturing are realizable. This paper gives an overview of the present potentials of MLM using 316L steel powder. While using powder material with a grain size of ≤ 5 µm this technique enables layer thicknesses from 5 to 7 µm. Due to the use of different exposure strategies and laser modes (pulsed and continuous radiation) high aspect ratios up to 260 could be realized with thin wall structures. Furthermore, the influence of laser mode and exposure sequence on the part density, surface quality and accuracy of lattice structures with a minimum wall thickness lower than 40 µm is analyzed.