Characterization of a laser-fabricated hypereutectic Al-Sc alloy bar

A 115 mm high bar was fabricated by laser metal deposition from Al-0.9 wt.% Sc powder. In the as-fabricated condition, the hardness decreased from 78 HV5 at the bottom to 34 HV5 at the top of the bar. At the top, the electrical conductivity was lowest, the amount of Sc in solution was highest and a subsequent ageing response was observed. It is concluded that for laser-fabrication of such alloys, the thermal history over the whole component must be understood and controlled. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.