Effect of Sr Modification Time on Microstructure and Properties of Near Eutectic Aluminum Alloy Electric Power Fitting Materials
Author of the article:LI Jie;ZHANG Jun
Author's Workplace：State Grid Beijing Electric Power Company,Beijing 100031,China;China Electric Power Research Institute,Beijing 100055,China
Key Words：modification time of Sr near eutectic Al-Si alloy electric power fitting materials
Abstract：
In the near-eutectic Al-Si-Mg alloy,Strontian(Sr)was added as a modifier.The effect of Sr modification time on the microstructure and mechanical properties of the alloys were studied.The results show that Sr can make the eutectic silicon become flocculent in the as-cast state,and the particle microstructure became finer after heat treatment.However,with the increasing modification time,the content of Magnesium(Mg)and Sr was burning lost gradually,which caused the effect of strengthening and modification decreased,so did mechanical properties.The best comprehensive mechanical properties of the alloy were observed after being modified for an hour,which the tensile strength is 325.6 MPa and the elongation is 8.3%.
