Enhancing strain hardening in TiVZr lightweight medium entropy alloys with Mn-induced maze-like nanostructure

Although lightweight high/medium entropy alloys (HEAs/MEAs) with a body-centered cubic (BCC) structure are a promising class of structural materials, their actual applications are limited due to their low strain-hardening ability. This work proposes a method of enhancing the strain-hardening ability of TiVZr lightweight MEA by a small amount of Mn element. The TiVZr0.1Mn0.1 exhibits a “maze-like” nanostructure that promotes dislocation multiplication during deformation, resulting in improved strength, strain hardening ability, and uniform elongation (>10 %). The considerable difference in lattice parameters between the Mn and TiVZr solid solution matrix contributes to significant solid solution strengthening, demonstrating a high specific tensile yield strength (∼180 MPa cm3/g). •The effect of Mn on the microstructure and properties of TiVZr MEA was reported.•Compared to TiVZr0.1, the TiVZr0.1Mn0.1 exhibits a “maze-like” nanostructure.•The maze-like nanostructure promotes multiplication of dislocations.•The TiVZr0.1Mn0.1 shows excellent uniform elongation and strain hardening ability.