Abstract Scope |
It has been recognized that additively manufactured Ti alloys are most usually characterized by the presence of very coarse columnar grains, oriented in the build direction. The solution that has been developed in our current research involves the application of computational thermodynamics to identify which alloying additions to titanium alloys result in an increase in the freezing range of the given alloy base, such that a columnar to equiaxed transition (CET) may be effected. These alloying additions, which are mainly beta eutectoid formers, when added in critical concentrations cause a CET to occur, resulting in a relatively fine equiaxed microstructure. The amounts of required solute additions usually exceeds their solubility limits, and, so, heat-treatments are required subsequent to the additive manufacturing process. Two types of alloys are being developed, the first with essentially identical properties as the (given) base alloy, and the second, alloys with enhanced mechanical properties. |