Recently developed high thermally conductive Al–Zn–Ca alloys were consolidated from powders through the laser powder bed fusion (LPBF) method. Particular attention is paid to the effect of Zn + Ca content on the defectiveness and mechanical properties of the printed samples. It was found that the printed samples of the rated composition Al–6Zn–6Ca (wt.%) were characterized by the presence of a large number of large cracks and demonstrated brittle behavior under tension loading. The total crack length increased with decreasing energy density, which is atypical for LPBF-printed materials. In printed samples with reduced zinc and calcium content of the rated composition Al–3Zn–4Ca, cracks do not form, and the ductility improves slightly (relative elongation up to 4.5%). Annealing at 400 °C for 1 h of the Al–3Zn–4Ca samples printed with a lower volumetric energy density provided a good combination of strength and ductility as well as a ductile fracture behavior.
Rogachev et al. (Mon,) studied this question.