文献类型：期刊文献

英文题名：Nacre-like surface nanolaminates enhance fatigue resistance of pure titanium

作者：Zhang, Yong[1];He, Chenyun[1];Yu, Qin[2];Li, Xiao[1];Wang, Xiaogang[3];Zhang, Yin[4];Wang, Ji[1];Jiang, Chao[3];Jia, Yunfei[1];Zhang, Xian-Cheng[1];Sun, Binhan[1];Ritchie, Robert O.[2];Tu, Shan-Tung[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Minist Educ, Key Lab Pressure Syst & Safety, Shanghai 200237, Peoples R China;[2]Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA;[3]Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Technol Vehicle, Changsha 410082, Peoples R China;[4]Peking Univ, Coll Engn, Dept Mech & Engn Sci, State Key Lab Turbulence & Complex Syst,BIC ESAT, Beijing 100871, Peoples R China

年份：2024

卷号：15

期号：1

外文期刊名：NATURE COMMUNICATIONS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:001290126100009)】；

基金：We thank C. Xu and D. Pan for assistance in performing in-situ fatigue crack growth experiments. This work was supported by the National Key Research and Development Project (No. 2022YFB4600019, 2023YFB3712100), National Natural Science Foundation of China (No. U21B2077, No. 52275147, No. 52321002, No. 52222505, No. 52122505), Natural Science Foundation of Shanghai (No. 23ZR1415500)

语种：英文

摘要：Fatigue failure is invariably the most crucial failure mode for metallic structural components. Most microstructural strategies for enhancing fatigue resistance are effective in suppressing either crack initiation or propagation, but often do not work for both synergistically. Here, we demonstrate that this challenge can be overcome by architecting a gradient structure featuring a surface layer of nacre-like nanolaminates followed by multi-variant twinned structure in pure titanium. The polarized accommodation of highly regulated grain boundaries in the nanolaminated layer to cyclic loading enhances the structural stability against lamellar thickening and microstructure softening, thereby delaying surface roughening and thus crack nucleation. The decohesion of the nanolaminated grains along horizonal high-angle grain boundaries gives rise to an extraordinarily high frequency (approximate to 1.7 x 103 times per mm) of fatigue crack deflection, effectively reducing fatigue crack propagation rate (by 2 orders of magnitude lower than the homogeneous coarse-grained counterpart). These intriguing features of the surface nanolaminates, along with the various toughening mechanisms activated in the subsurface twinned structure, result in a fatigue resistance that significantly exceeds those of the homogeneous and gradient structures with equiaxed grains. Our work on architecting the surface nanolaminates in gradient structure provides a scalable and sustainable strategy for designing more fatigue-resistant alloys. Most strategies to improve fatigue resistance address either crack initiation or growth. Here, the authors design a gradient-structured Ti with nacre-like surface nanolaminates that increase fatigue performance by suppressing both stages of cracking