Fatigue Strengths of 14S-T4 Aluminum Alloy Subjected to Biaxial Tensile Stresses
Abstract
The purpose of this investigation was to determine the influence of biaxial tensile stresses on the fatigue strength of a 14S-T4 aluminum alloy when subjected to various ratios of biaxial stresses. The effect upon the fatigue strength of varying the ratio of the biaxial stresses was studied. The biaxial fatigue stresses were produced by applying simultaneously a pulsating internal pressure and a fluctuating axial tensile load to a thin-walled tubular specimen. The maximum and minimum values of the longitudinal and circumferential stresses were kept in phase by adjusting the testing machine. The dynamic loads were applied to the specimen by a specially designed testing machine. The fatigue strengths and S-N diagrams were obtained up to about 10 (exp 7) cycles for four principal stress ratios. The test results show that the fatigue strength is greatly affected by the anisotropy of the material. For this reason, it was found that the fatigue strength of the material in the circumferential direction was about two-thirds of the fatigue strength in the longitudinal direction. The test results for the 14S-T4 extruded tubing did not agree with any particular theory of failure. However, if the anisotropy of the material is considered the results are sufficiently close to the stress theory to permit its use in design.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1952
- Accession Number
- ADA557593
Entities
People
- Joseph Marin
- W. P. Hughes
Organizations
- Pennsylvania State University