Welding and environmental test condition effect in weldability and strength of Al alloy

Tensile and yield strengths did not have a great effect on tested temperature at +25 °C to −85 °C, but increased much at −196 °C. Also, strain tended to increase as test temperature decreased. Shielding gas composition dose not have a great influence on mechanical properties. The absorbed energy of weld metal-notched specimens did not depend on test temperature and mixing shield gas. On the other hand, the other specimens showed that as temperature was lower, absorption energy increased slightly up to −85 °C but the energy decreased so much at −196 °C. There is about 4.25% deviation between fatigue life analysis result and experimental result.