Chuanxi Ren, Shan Jin, Yifan Chen, Hengchao Shi, Yating Ran, Zizheng Song, Xingdong Dan, Qi Liu, Yixuan Sun, Haoran Sun, Zhiyuan Liu, Yuntian Zhu, Zibin Chen
Enhancing the fatigue resistance of metals remains a significant challenge in materials engineering. This study demonstrates that titanium exhibits remarkable fatigue resistance when heterostructures are introduced via additive manufacturing. Compared to homogeneously structured titanium, heterostructured titanium shows a remarkable 141% improvement in fatigue strength and a 53% enhancement in fatigue ratio. The heterostructure promotes the formation of high-density geometrically necessary dislocations, leading to hetero-deformation-induced strengthening under cyclic loading. This process enhances structural stability, suppressing fatigue crack initiation and propagation, thus improving fatigue resistance. These findings suggest that heterogeneity is a promising strategy for enhancing fatigue resistance across various alloy systems.