INTERACTION OF SOLUTE ATOMS WITH DISLOCATIONS IN ALUMINUM-MAGNESIUM ALLOYS UNDER FATIGUE LOADING,
Abstract
Torsional fatigue experiments were carried out with aluminum-magnesium alloys containing 0.52, 0.91, 3.46, and 5.15 per cent magnesium at the quenched state, and fatigue curves were determined. Experimental results showed that, in the cases of the specimens containing 0.52 per cent and 0.91 per cent magnesium, delta E drops with an increase of the stress cycle N when the torsion strain is small. However, when the torsion strain is higher, the curve keeps flat at the beginning, but delta E increases subsequently and becomes stable after a fairly high value is reached. As the magnesium content in the specimen is 3.46 per cent, the change of the delta E-N curve is similar to that of the Al-4 per cent Cu alloy when the torsion strain is not too high. When the torsion strain is sufficiently large, delta E increases at the beginning and decreases after it passes through a maximum value. The change of the delta E-N curve of the specimen containing 5.15 per cent magnesium is similar to that of the Al-4 per cent Cu alloy and no peak value was observed on the curve with the highest torsion strain. The Tm value shows an initial increase for specimens with all the magnesium contents studied. These results can all be explained with the assumption that 'atmospheres' of solute atoms are formed because of the gradual migration of magnesium atoms to dislocations during fatigue loading. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 16, 1967
- Accession Number
- AD0676568
Entities
People
- Huang Yuan-shih
- Ko T'ing-sui
- Wang Chung-kang
Organizations
- National Air and Space Intelligence Center