Improved mechanical properties of AlSi7Mg/nano-SiCp composites fabricated by selective laser melting

AlSi7Mg is one of the most widely used aluminum alloys. However, its moderate strength limits its use as a structural material for critical parts. Most mechanisms used to strengthen the material sacrifice its ductility. In situ reactions during the selective laser melting (SLM) process rectify the trade-off by introducing dislocations around the subgrain boundaries and nano-twin planes in the by-product Si phase. This work was the first attempt to reinforce AlSi7Mg by nano-SiC particles fabricated by SLM. In addition, the rapid solidification rate caused solid solution strengthening, fine-grain strengthening and precipitation strengthening, which also contributed to the mechanical properties. (C) 2019 Elsevier B.V. All rights reserved.