Homogenization Treatment to Optimize the Microstructures of the Al-3.5Cu-1.5Li Alloy and Analysis of Al₃Zr Precipitates

Abstract:

The microstructure evolution and composition distribution of the cast Al-3.5Cu-1.5Li-0.11Zr alloy during single-step and double-step homogenization were studied with the help of the optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and transmission electron microscopy (TEM) methods. The results show that severe dendrite segregation exists in the experimental alloy. Six different homogenization treatments, conventional one-stage homogenization and double-stage homogenization are carried out, and the best homogenization treatment of the experimental alloys was achieved. Moreover, the precipitation of Al₃Zr particles was significantly different after two kinds of homogenization in the experimental alloy. Compared with the single-stage homogenization, a finer particle size and distribution more diffuse of Al₃Zr particles can be obtained in the double-stage homogenization treatment.

• Periodical: Materials Science Forum (Volume 921)
• Pages: 195-201
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.921.195
• Online since: May 2018
• Authors: Jin Jun Xu, Mang Jiang*
• Keywords: Al-3.5Cu-1.5Li Alloy, Al₃Zr Precipitate, Homogenization Treatment

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