Effect of Strontium and T6 Heat Treatment on Structure and Performance of Al-11.6Si-0.5Mg Alloy

Abstract:

In this study, Strontium (Sr) was added as modifier during the casting of Al-11.6Si-0.5Mg alloy, and the effect of T6 heat treatment on microstructure and performance of alloy was also investigated. The results showed that the 0.3% Al-8%Sr master alloy can refine effectively the α-Al dendrite and eutectic structure; the best economic process of T6 heat treatment is solution at 535°C for 6 hrs., and water cooling at 50~60°C,aging at 160°C for 6 hrs , then air cooling. After Sr modification and T6 heat treatment, the mechanical properties of alloy are improved remarkably, i.e., the tensile strength increased to 348MPa from 183MPa before modification and the elongation raises from 3.0% to 6.5%. So this alloy is applied to the strain clamp products in electric power fitting industry.

• Periodical: Materials Science Forum (Volume 749)
• Pages: 1-6
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.749.1
• Online since: March 2013
• Authors: Ji Xing Lin, Jun Ping Zhang, Li Yuan Niu, Da Ren Sun, Zi Mu Shi, Yong Li, Guang Yu Li
• Keywords: Near Eutectic Al-Si Alloy, Sr Modification, T6-Heat Treatment

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