INVESTIGATION TOWARD OBTAINING SIGNIFICANTLY HIGHER MECHANICAL PROPERTIES OF AS-WELDED JOINTS IN HIGH-STRENGTH, HEAT TREATABLE ALUMINUM ALLOYS
Abstract
This report describes the second phase of an investigation to improve welds in high strength aluminum alloys such as 7075 and 7178. Direct current, straight polarity, helium shielded tungsten arc automatic welding was preferred for most consistent results, although highest individual weld strengths were achieved with carefully controlled consumable electrode short arc technique. High travel speeds, with TIG welding, decreased weld strength because of small hot-short cracks. Cold working of welds before aging often caused cracks and had no beneficial effect on strength. Locally heat treating welds with a low power arc before aging increased ductility in both tensile and bulge tests. Strength was about equivalent to no heated welds. Base metal properties determined after short time exposure to high temperatures were used to predict joint designs for local heat treatments.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 20, 1963
- Accession Number
- AD0418106
Entities
People
- F. R. Collins
Organizations
- Alcoa