Contour laser strategy and its benefits for lattice structure manufacturing by selective laser melting technology

Abstract

This paper deals with the research of the Selective Laser Melting (SLM) scanning strategy to produce lattice structures from AlSi10Mg powder material. Nowadays, most of the SLM end-users use the laser strategy and parameters recommended by powder or machine suppliers to produce different components. However, this setup can cause material and shape imperfection, especially in the case of low-volume lattice structures. In this study, the default meander scanning strategy for AlSi10Mg material was changed to contour strategy and its main SLM process parameters were developed. Commonly used experiments were modified to consider the lattice structure's shape and dimension. The results showed that by using developed parameters, i.e., recommended range of input linear energy of 0.25-0.4 J/mm; track width based on strut diameter, input linear energy and the orientation of strut; the overlap of the laser contour tracks of 35% and inside-out direction; it is possible to produce lattice structures with high material density (more than 99.8%) and low surface roughness in a wide range of strut diameters from 0.6 to 3 mm. The differences in lattice structure production of vertical and inclined struts are described and discussed in relation to the SLM process during powder melting with use of thermal transient simulation.