Tailored thermal treatment for SLM built aluminum alloy product

Selective laser melting (SLM) induces microstructures finer than the ones obtained by conventional casting methods, due to faster cooling rates. Hence, dedicated thermal treatments should be designed in order to optimize the material properties. In this work new thermal treatments, specifically designed for selective laser melted parts in AlSi10Mg, have been investigated. The samples were analyzed by differential scanning calorimetry and scanning electron microscopy in order to correlate the characteristic transformation peaks and the corresponding microstructure. The precipitation of Mg2Si as well as the rupture and spheroidization of the silicon network, present in the matrix, were recognized. Consequently, dedicated thermal treatments were proposed, as a lower temperature alternative to be applied as postprocessing for AlSi10Mg SLM built components. The obtained results were compared with the effects of conventional thermal treatments in terms of obtained microstructure and mechanical properties.