Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7951957 | Journal of Materials Science & Technology | 2018 | 24 Pages |
Abstract
The fatigue behavior of aluminum alloy 7050-T7451 single lap four-bolted joints was studied by high-frequency fatigue test and finite element (FE) methods. The fatigue test results showed that a better enhancement of fatigue life was achieved for the joints with high-locked bolts by employing the combinations of cold expansion, interference fit, and clamping force. The fractography revealed that fatigue cracks propagated tortuously; more fatigue micro-cliffs, tearing ridges, lamellar structure were observed, and fatigue striation spacing was simultaneously reduced. The evaluation of residual stress conducted by FE methods confirmed the experimental results and locations of fatigue crack initiation. The extension of fatigue lives can be attributed to the evolution of fatigue damage and effect of beneficial compressive residual stresses around the hole, resulting in the delay of crack initiation, crack deflection, and plasticity-induced crack closure.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Chemistry
Authors
Xiaomei Liu, Hao Cui, Shangzhou Zhang, Haipo Liu, Gaofeng Liu, Shujun Li,