Creep behaviour of a AlSiMg alloy produced by additive manufacturing

The present study aims at investigating the effect of the peculiar microstructure of additive manufactured samples on the creep behavior of a AlSiMg alloy. Constant load creep experiments were carried out between 150 and 205°C on an AlSiMg alloy produced by Powder Bed Fusion Additive Manufacturing (AM). The samples were mostly strained up to rupture, although in some cases the test were interrupted at the early onset of the tertiary region. Analyzing the time-to rupture, in the different load and temperature conditions, as a function of the applied stress, it can be clearly seen that the alloy produced by AM is substantially comparable, in terms of time to rupture, with an alloy of similar composition, tested in the die-cast state. The high values of the stress exponent suggest that the creep behavior is strongly affected by the presence of secondary-phase particles.