The stress-controlled fatigue tests are carried out at a stress ratio of 0.1 and a frequency of 10 Hz,and span both low-cycle and high-cycle regimes by varying the applied stress amplitudes.The high-cycle fa-tigue regime gives a fatigue strength of 497 MPa and a fatigue ratio of 0.44.At equivalent conditions,the alloy's fatigue strength is greater than all other high-entropy alloys(HEAs)with reported high-cycle fatigue data,dilute body-centered cubic alloys,and many structural alloys such as steels,titanium al-loys,and aluminum alloys.Through in-depth analyses of crack-propagation trajectories,fracture-surface morphologies and deformation plasticity by means of various microstructural analysis techniques and theoretical frameworks,the alloy's remarkable fatigue resistance is attributed to delayed crack initiation in the high-cycle regime,which is achieved by retarding the formation of localized persistent slip bands,and its good resistance to crack propagation in the low-cycle regime,which is accomplished by intrin-sic toughening backed up by extrinsic toughening.Moreover,the stochastic nature of the fatigue data is neatly captured with a 2-parameter Weibull model.

Shuying Chen;Weidong Li;Ling Wang;Tao Yuan;Yang Tong;Ko-Kai Tseng;Jien-Wei Yeh;Qingang Xiong;Zhenggang Wu;Fan Zhang;Tingkun Liu;Kun Li;Peter K.Liaw

Institute for Advanced Studies in Precision Materials,Yantai University,Yantai 264005,China;Department of Materials Science and Engineering,The University of Tennessee,Knoxville,TN 37996,USA;Department of Industrial and Systems Engineering,Ohio University,Athens,OH 45701.USA;Department of Materials Science and Engineering,High Entropy Materials Center,National Tsing Hua University,Hsinchu.30013,Taiwan,China;State Key Laboratory of Pulp and Paper Engineering,South China University of Technology,Guangzhou 510640,China;School of Light Industry and Engineering,South China University of Technology,Guangzhou 510640,China;College of Materials Science and Engineering,Hunan University,Changsha 410082,China;WPI Advanced Institute for Materials Research,Tohoku University,Sendai 980-8577,Japan;State Key Laboratory of Mechanical Transmission,Chongqing University,Chongqing 400044,China

材料科学技术（英文版）

[1]Shuying Chen;Weidong Li;Ling Wang;Tao Yuan;Yang Tong;Ko-Kai Tseng;Jien-Wei Yeh;Qingang Xiong;Zhenggang Wu;Fan Zhang;Tingkun Liu;Kun Li;Peter K.Liaw-.Stress-controlled fatigue of HfNbTaTiZr high-entropy alloy and associated deformation and fracture mechanisms)[J].材料科学技术（英文版）,2022(19):191-205

HfNbTaTiZr,tigue

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