The role of alloying additives and aging treatment on the impact behavior of 319 cast alloy

This article investigated the effects of alloying additives on the impact toughness of as-cast and heat-treated 319 alloys. The results revealed that the impact energy decreases with increasing the level of Fe, Mn, and Mg additions. The aged alloys at 180 °C had a slightly increase in the impact energy compared to the as-cast alloys. The aged alloys containing combined additions of Fe–Mn and Fe–Mg displayed a similar variation in the impact energy at different aging temperatures and times. The fracture surface of the alloys was strongly controlled by the morphology of eutectic Si and Cu- and Fe-rich phases.

Research highlights
► Influence of additives on the impact toughness of 319 alloy.
► Addition of 0.4% Mn improves the impact energy for both non-modified and modified alloys.
► Addition of 0.3% Mg decreases the impact energy, with respect to Fe content.
► 319 containing 0.2% Fe aged at 180 °C/12 h display the highest impact energy of all the alloys studied.
► Fracture surface is controlled by the morphology of eutectic Si and Cu- and Fe-rich phases.