TY - CONF A1 - Laumer, Tobias A1 - Schmidt, Michael A1 - Stichel, Thomas T1 - Influence of temperature gradients on the part properties for the simultaneous laser beam melting of polymers T2 - Proceedings of Laser in Manfacturing Conference 2015, June 22 - June 25, 2015 Munich, Germany N2 - By Laser Beam Melting of polymers (LBM), parts with almost any geometry can be built directly out of CAD files without the need for additional tools. Thus, prototypes or parts in small series production can be generated within short times. Up to now, no multi-material parts have been built by LBM, which is a major limitation of the technology. To realize multi-material parts, new mechanisms for depositing different polymer powders as well as a new irradiation strategy are needed, by which polymers with different melting temperatures can be warmed to their specific preheating temperatures and be molten simultaneously. This is achieved by simultaneous laser beam melting (SLBM). In the process, two different materials are deposited next to each other and preheated a few degrees below their melting temperatures by infrared emitters and laser radiation (λ = 10.60 µm), before in the last step the two preheated powders are molten simultaneously by an additional laser (λ = 1.94 µm). So far, multi-material tensile bars have been realized and analyzed regarding their boundary zone between both materials. The experiments showed that the temperature gradients in the boundary zone and along the building direction seem to be of great importance for the process stability and the resulting part properties. Therefore, a detailed analysis of the occurring temperature gradients during the process is needed to identify adequate process adjustments regarding the temperature controlling. To analyze the temperature gradients, thermocouples positioned inside the powder bed are used. By varying the temperature of the building platform, the influence of different temperature gradients on the resulting part properties is shown. KW - additive manufacturing KW - laser beam melting of polymers KW - multi-material parts Y1 - 2015 UR - https://opus4.kobv.de/opus4-oth-regensburg/frontdoor/index/index/docId/4129 UR - https://www.wlt.de/lim/Proceedings/Stick/PDF/Contribution241_final.pdf ER -