Rapid manufacturing of lattice structures with selective laser melting

Since the development of layered freeform manufacturing processes some technologies have emerged such as the Selective Laser Melting process (SLM) which uses layers of metal powder to manufacture 3D-objects from CAD-data by melting targeted geometries. The main goal using this process is to obtain functional products from engineering materials that feature desired properties such as given strength, hardness, surface roughness and residual stress behaviour. Rapid production with short throughput times due to only few process steps, a high individuality and a high degree of geometric freedom are considered to be its major advantages. However one disadvantage to all laser-based freeform manufacturing is the immense consumption of time since only considerably small quantities of material can be processed per time unit. Therefore it is desirable to review oldfashioned engineering design rules and develop part geometries that allow for hollow shaped parts with interior lattice structures providing the part with virtually the same stiffness and strength. Thus the process cost could be massively cut down due to reduced production time and less need for costly powder material. The SLM-process is meeting the requirements to fulfil this intention. Based on using fiber laser technology that delivers high beam quality the process is capable of producing thin walled structures of high tensile strength. Here development, production and testing of such lightweight yet sustainable SLM-parts will be presented along with their possible applications.