Efficient Solid‐Solution Strengthening Enhanced the Wear Resistance of Ti–Ta Alloys Manufactured by Laser Powder Bed Fusion

Ti is a paramount material in biomedical implants owing to its lightweight, superior corrosion resistance, and biocompatibility. Nevertheless, inferior plastic shear‐resistance and strain‐hardening cause insufficient wear resistance in pure Ti, which easily causes implant loosening or failure, thereby posing a profound bottleneck for applications. Therefore, this study proposed a feasible process route of mechanical alloying (MA) and laser powder bed fusion (LPBF) for developing Ti–Ta alloys with a β‐phase solid‐solution, aiming to solve the wear resistance dilemma. During MA, severe plastic deformations stemming from mechanical collisions induced dislocation accumulations inside powders, which provided sufficient atomic‐scale channels and driving force for overstepping solid‐solubility limits of Ta solute. Consequently, a β‐phase solid‐solution, accompanied by fine grains (∼0.56 μm), was constructed within in situ alloyed Ti–Ta powders. In subsequent consolidation of powders, the extremely high temperature gradient and transient solidification nature of the LPBF process perpetuated the non‐equilibrium β‐phase solid‐solution, thus constructing an α + β uniform microstructure in as‐printed Ti–Ta alloys. This unique structure triggered effective solid‐solution and grain‐refinement strengthening, thereby leading to continuous dislocation accumulations near phase boundaries, which synergistically endowed Ti–Ta alloys with enhanced wear resistance (friction coefficient ∼0.46). Overall, this study provides a feasible strategy for manufacturing wear‐resistant Ti alloys via extended solid‐solution and grain‐refinement.