Strong and ductile Al-Mn-Mg-Sc-Zr alloy achieved in fabrication-rate enhanced laser powder bed fusion

The high cost of laser powder bed fusion (LPBF) fabricated high-strength Sc containing aluminium alloy hinders its applications. To reduce the cost, we reported a LPBF fabricated strong and ductile Al-Mn-Mg-Sc-Zr alloy using large layer thicknesses to improve the fabrication efficiency on coarse powder particles. A high relative density exceeding 99.2% was achieved at layer thicknesses up to 120 mu m. In post-process heat-treated specimens, the yield strength only had a slight 6% decrease from layer thickness of 30 to 120 mu m; such a decrease in strength was attributed to the larger grain size resulted from the adopted larger layer thickness. The fabricated sample at layer thickness of 120 mu m still exhibited high tensile yield strength of 472 MPa and fracture strain of similar to 10%. This work showed a successful application of improving the LPBF fabrication efficiency of highstrength Al-Mn-Mg-Sc-Zr alloy using large layer thickness in LPBF process.