Heat Treatment of Additionally Manufactured Aluminium Alloys

摘要

Additive manufacturing (AM) provides several beneficial properties for metallic materials. Fastsolidifying rates result in a fine microstructure, enabling higher mechanical properties when comparedto traditional methods. AM method may however also lead to anisotropy of some properties. A hightemperature solution annealing (SA) heat treatment is the traditional way to homogenize themicrostructure and to distribute alloying elements into the aluminium matrix. Mechanical propertiescan be further enhanced with ageing treatments. The breakup of the fine lamellar AM microstructure isobserved in the very early stages of SA heat treatments. Further coarsening of the microstructurehappens when SA is continued, which can have undesirable effects on mechanical properties. A novelheat treatment cycle including a shortened SA step is proposed in order to retain the benefits of thefine AM structure. The dependence of tensile properties on build direction can also be diminished bysaid heat treatment.