Initiation and Propagation Behaviors of Small Fatigue Crack in Titanium Alloy TC4

Abstract:

The initiation and propagation behaviors of small fatigue crack in TC4 were investigated in the present work. Surface replication on the basis of a two-part silicon mixture and confocal laser scanning microscope were used to record and observe the small crack initiation and growth processes at room temperature in air. Results showed that surface cracks initiated from the interfaces between α and β phases. When the crack lengths were below ~200 μm, the crack growth rates exhibited large oscillations and temporary retardations due to the presence of α/β interfaces. The corner crack propagated much faster and might have shielding effect on the surface crack.

• Periodical: Key Engineering Materials (Volume 795)
• Pages: 9-14
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.795.9
• Online since: March 2019
• Authors: Lei Zhu*, Xu Teng Hu, Rong Jiang, Ying Dong Song, Shou Dao Qu
• Keywords: Crack Growth, Crack Initiation, Small Fatigue Crack, Surface Replica, Titanium Alloy TC4

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