Crack Nucleation in β Titanium Alloys under High Cycle Fatigue Conditions - A Review

6th International Conference on Fracture Fatigue and Wear

Benjamin, Rohit^1 ; Nageswara Rao, M.^2

Department of Aerospace Engineering, RVCE, Bengaluru

Karnataka, India^1

School of Mechanical Engineering, VIT University, Vellore

Tamil Nadu, India^2

关键词: Aerospace sectors;    Beta titanium alloy;    Fatigue-crack nucleation;    High cycle fatigue;    Loading condition;    Microstructural features;    Precipitate free zones;    Subsurface cracks;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/843/1/012048/pdf
DOI  :  10.1088/1742-6596/843/1/012048

来源: IOP

【 摘 要 】

Beta titanium (β-Ti) alloys have emerged over the last 3 to 4 decades as an important class of titanium alloys. Many of the applications that they found, particularly in aerospace sector, are such that their high cycle fatigue (HCF) behavior becomes critical. In HCF regime, crack nucleation accounts for major part of the life. Consequently it becomes important to understand the mechanisms underlying the nucleation of cracks under HCF type loading conditions. The purpose of this review is to document the best understanding we have on date on crack nucleation in β-Ti alloys under HCF conditions. Role of various microstructural features encountered in β-Ti alloys in influencing the crack nucleation under HCF conditions has been reviewed. It has been brought out that changes in processing can result in changes in microstructure which in turn influence the time for crack nucleation/fatigue life and fatigue limit. While majority of fatigue failures originate at the surface, subsurface cracking is not uncommon with β-Ti alloys and the factors leading to subsurface cracking have been discussed in this review.