Influence of microstructure on strain controlled low cycle fatigue crack initiation and propagation of Ti-55531 alloy. (March 2022)

• Record Type: Journal Article
• Authors: Xu, Zilu; Huang, Chaowen; Wan, Mingpan; Tan, Changsheng; Zhao, Yongqing; Ji, Shengli; Zeng, Weidong
• Is Part Of: International journal of fatigue. Volume 156(2022)
• Publication Date: 2022-03
• Subjects: Ti-55531 alloy -- Microstructure -- Low cycle fatigue -- Crack initiation -- Crack propagation; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2021.106678
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: Stacking faults would promote LCF microcracks nucleation of Ti-55531 alloy. LCF microcracks nucleation and growth are dependent on both strain level and microstructure. Fatigue life of BM is lower than that of LM at high strain levels (>0.866%). LCF damage of Ti-55531 alloy is dramatically affected by α phase features. Abstract: Low cycle fatigue (LCF) crack initiation and propagation behavior of Ti-55531 alloy with lamellar and bimodal microstructures were comparatively investigated at room temperature. Results indicated that the two microstructures displayed different sensitivity to the change of cyclic strain, which resulted in significantly different cyclic deformation, fatigue crack nucleation, and crack propagation behavior of two microstructures. Finally, it was found that cyclic lives of two microstructures were entirely different. Moreover, besides slips and deformation twins, stacking faults promoting cracking of αs /β interface may be another important LCF microcrack nucleation mechanism of Ti alloys, which hasn't been revealed by other researchers.