中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 23 No. 11 November 2013 |
（1. Institute of Advanced Forming, Nanchang University, Nanchang 330031, China;
2. Jiangxi Key Laboratory for Advanced Copper and Tungsten Materials,
Jiangxi Academy of Sciences, Nanchang 330029, China）
Abstract:The effects of rare earth samarium (Sm) additions on the microstructure and mechanical properties of as-cast Al-Si-Cu alloy were investigated by optical microscopy and scanning electron microscopy (SEM). The results show that Sm can effectively refine the α(Al) dendrite and the eutectic silicon. In addition, the shape of iron-rich phases changes from the Chinese script-like to slender-like ones and the volume fraction of iron-rich phases is decreased by the addition of Sm. Two kinds of Sm-rich intermetallics are found: AlSiSm and AlSiCuSm. The plate-like AlSiCuSm phase always associates with the needle-like AlSiSm phase. The mechanical properties are improved by the addition of Sm, and the good ultimate tensile strength (220 MPa) and elongation (3.1%) are obtained from the Al-Si-Cu-1.0Sm alloy.
Key words: aluminum alloys; rare earth; samarium; microstructure; mechanical properties
