| Abstract Scope |
Alloying and processing of titanium deliver a broad set of desired strengthening effects. However, the known hardening mechanisms also display serious limitations, with the most noticeable being ductility reduction, e.g. increase in concentration of the interstitial solutes such as O or N by 0.5 wt.% reduces the elongation to failure by 40% and a relatively high content of alloying elements increases density, material cost and difficulty in recycling. In this work, in contrast to several recent design strategies, we propose an apprach based on a microalloying approach using a single transition element: rhenium (Re), which appears to be a powerful β-stabilizing element with one of the lowest possible formation energies in β-titanium.The main idea of this approach is to activate both stron precipitation strengthening with nanoscale β particles located inside the α matrix and extremely efficient solute strengthening of β phase. Such microstructures together with substantial grain refinement observed in the model, recrystallized Ti–Re alloys result in a 2.8 times increase in yield strength, relative to pure Ti and a high ~ 35% elongation obtained at 0.5 wt.% (0.13 at.%) Re content. It is expected that similar properties can be obtained using other strong beta-stabilizers, making this method a universal way to improve the mechanical properties of Ti-based materials. |