文献类型：期刊文献

英文题名：Ultrasonic surface rolling improves tensile properties but reduces rotating bending fatigue strength in a titanium alloy

作者：Huang, Ji Zhang, Zhong Yang, Jiang Wen, Xin Liu, Dan Li, Tianxin Wan, Mingpan Chen, Junyu Huang, Chaowen

第一作者：Huang, Ji

通信作者：Huang, CW[1]

机构：[1]Guizhou Univ, Natl & Local Joint Engn Lab High Performance Met S, Guiyang 550025, Peoples R China;[2]Guizhou Inst Technol, Sch Mat & Energy Engn, Guiyang 550003, Peoples R China;[3]Guizhou Anda Aviat Forging Co Ltd, Anshun 561000, Peoples R China;[4]Nanyang Technol Univ, Sch Mech & Aerosp Engn, Singapore 639798, Singapore

第一机构：Guizhou Univ, Natl & Local Joint Engn Lab High Performance Met S, Guiyang 550025, Peoples R China

通信机构：corresponding author), Guizhou Univ, Natl & Local Joint Engn Lab High Performance Met S, Guiyang 550025, Peoples R China.

年份：2026

卷号：1057

外文期刊名：JOURNAL OF ALLOYS AND COMPOUNDS

收录：;EI(收录号：20260720079937);WOS:【SCI-EXPANDED(收录号:WOS:001693059200001)】；

基金：This work was supported by the National Natural Science Foundation of China (Nos. 52261025 and 52474402) , the Major Science and Technology Special Project of Guizhou Province (No. Qiankehe Rencai XKBF [2025] 008) , the Outstanding Young Science and Technology Talent Program of Guizhou Province (No. Qiankehe Platform Rencai YQK [2023] 009) , the China Scholarship Council (CSC Selection [2024] 42-202406670003) , and the Guizhou Province Graduate Education Innovation Program (2024YJSKYJJ084) . The SEM technical support from Shaanxi Qingyan Youce Technology Co., Ltd is acknowledged.

语种：英文

外文关键词：Dual-phase titanium alloy; Ultrasonic surface rolling processing; Gradient microstructure; Rotational bending high cycle fatigue; Fatigue crack initiation and propagation mechanism

摘要：Ultrasonic surface rolling processing (USRP) was employed to generate a gradient nanostructured surface layer on TC21 alloy, enabling a systematic evaluation of its coupled effects on tensile and fatigue performance. The results reveal that microstructural gradients exert a decisive influence on the evolution of rotational bending high-cycle fatigue (RBHCF) damage. Although USRP significantly improved surface integrity-characterized by reduced roughness, elevated compressive residual stresses, and a steep hardness gradient-and yielded a 3 % increase in elongation together with a tensile strength of 1277 MPa, the RBHCF strength decreased by 7.7 % relative to the untreated alloy. Microstructural and fractographic analyses demonstrate that the pronounced mechanical-property gradient between the deformed surface layer and the softer substrate generates interfacial stress concentrations that promote fatigue crack initiation. Crucially, selective dislocation accumulation at primary alpha (alpha p) and secondary alpha (alpha s) phases interfaces, combined with the micro-scale strain mismatch at alpha p/beta trans (beta transformed microstructure) and alpha s/beta r (retained beta matrix) interfaces, leads to localized stress amplification. These mechanisms collectively accelerate fatigue crack propagation within the gradient-affected zone. This study underscores the critical role of microstructural gradient design in determining fatigue behavior and offers new insights into optimizing surface severe plastic deformation processes for fatigue-critical applications.