Abstract
The influence of microstructure homogeneity on crack initiation behavior under high-cycle fatigue (HCF) test at room temperature was studied in Ti-55531 alloy with lamellar microstructure by TEM and SEM. The results show that the HCF strength of Ti-55531 alloy could be as high as 639 MPa. However, a small amount of grain boundary (GB) α and a large number of inhomogeneous regions in microstructure significantly affect the HCF behavior of lamellar Ti-55531 alloy. Fatigue microcracks mainly initiate at interfaces between αs and βr phases owing to their different structures and properties. Moreover, a small amount of microcracks initiate at GB α and αs phases during fatigue.
Original language | English |
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Pages (from-to) | 663-668 |
Number of pages | 6 |
Journal | Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering |
Volume | 46 |
Issue number | 3 |
State | Published - 1 Mar 2017 |
Keywords
- Crack initiation
- High-cycle fatigue
- Microstructure homogeneity
- Ti-55531 titanium alloy