بررسي مقدار بهينه استرانسيم در توليد قطعات ريختگي آلومينيوم A319 با خواص مكانيكي بالا

Optimum Sr-Concentration in Casting of Modified A356 Alloy with High Mechanical Properties

Modification of Al-Si alloys with Sr changes the morphology of eutectic Si from large acicular to fine fibrous shape thus it should increase considerably the mechanical properties of the alloys. The effect of Sr-modification with different amount of Sr on the micro structure and mechanical properties or A356 alloy has been studied. In order to have a full modified Si morphology, the optimum Sr-concentration has been found to be about 0.01-0.02wt%. However the Sr-modification nearly decreased the strength of heat treated A356 alloy castings, in particular when used high amount of Sr.