Journal of the Korean Society of Safety (한국안전학회지)
- Volume 14 Issue 2
- /
- Pages.19-25
- /
- 1999
- /
- 1738-3803(pISSN)
- /
- 2383-9953(eISSN)
A Study on the Anisotropy of Al 7075 Rolling Material in Fatigue Crack Growth Process
Al 7075 압연재의 피로균열 성장과정에서의 이방성에 관한 연구
Abstract
The research has extracted two kinds of specimen, one is rolling direction material(R-material) and the other rectangular of rolling direction(V-material), from Al alloy 7075 rolled. We have come to a conclusion by measuring crack propagation behavior with movement type microscope and Replica. 1) R-material shows 130% higher, approx. 39.2MPa in fatigue strength than V-material, approx. 29.4MPa. 2) In crack proportion, contrary to V-material growing directly toward specimen axis, R-material grows neared to shear direction. 3) The life proves that R-material is approx. 122% higher than V-material at 43.1MPa and approx. 135% higher at 47MPa. 4) The correlation between fatigue crack length and fracture life ratio applied to 'log(2a)=A+B (
Keywords