Cyclic deformation and fatigue behavior of 7075-T651 Al alloy with a gradient structure

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:822

Article

Liu, Zepeng¹  Zhang, Hongxia¹  Yan, Zhifeng¹  Liaw, Peter K.²  Dong, Peng¹ 

[1] Taiyuan Univ Technol, Coll Mat Sci & Engn, Taiyuan 030024, Peoples R China

[2] Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA

关键词: Aluminum alloy;    Surface treatment;    Cyclic deformation;    Fatigue-life evaluation;   

DOI  :  10.1016/j.msea.2021.141669

来源: Elsevier

【 摘 要 】

Fully reversed stress-controlled tension-compression fatigue experiments (R = -1) were conducted to study the cyclic deformation and fatigue behavior of 7075-T651 aluminum alloys with and without a surface mechanical rolling treatment (SMRT). The strain amplitude, ratcheting effect, and asymmetric behavior of base metal (BM) and SMRT specimens were analyzed. SMRT specimens showed more remarkable ratcheting effects and tension-compression asymmetry under high stresses. Fatigue tests showed that the fatigue strengths of 7075 Al alloys were increased significantly by the SMRT. Both BM and SMRT specimens presented a failure-mode transition from the intrusions and extrusions failure modes to the Al18Ti2Mg3 constituent phase. The hysteresis loop was utilized to obtain the plastic-strain amplitude. Furthermore, according to the cyclic-deformation behavior combined with the Manson-Coffin law, strain-life evaluation of BM and SMRT specimens under the stress-control is given.

【 授权许可】

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