The microstructure, mechanical properties and compression creep resistance of as-cast Mg-5Sn-2Ce-xZn（x=0, 2 wt.%, 4 wt.%） alloys were investigated in this paper. The results showed that the Ce-containing compounds w...The microstructure, mechanical properties and compression creep resistance of as-cast Mg-5Sn-2Ce-xZn（x=0, 2 wt.%, 4 wt.%） alloys were investigated in this paper. The results showed that the Ce-containing compounds were MgS nC e phase and an unknown phase, and they were the dominant intermetallics in as-cast Mg-5Sn-2Ce-xZn alloys. At x=0 wt.%, the Ce-containing compounds formed in interdendritic regions with the shape of rod. As the Zn content was increased to 2 wt.%, the Ce-containing compounds partly changed from rod-like to sheet-like. However, there were few further changes in the Ce-containing compounds with further increase in Zn content to 4 wt.%. Compared with Mg-5Sn-2Ce alloy, the tensile strength and elongation of the alloy containing 4 wt.% Zn increased by 39% and 112%, respectively, and the secondary creep rate（175 °C/55 MPa） decreased at least by an order of magnitude. These improvement could be attributed to the combined effects of the high content of Zn dissolving in a-Mg matrix and the modification of Ce-containing compounds by Zn addition.展开更多
基金Project supported by Science and Technology Support Program of Sichuan province(CN)(2009GZ0010)
文摘The microstructure, mechanical properties and compression creep resistance of as-cast Mg-5Sn-2Ce-xZn（x=0, 2 wt.%, 4 wt.%） alloys were investigated in this paper. The results showed that the Ce-containing compounds were MgS nC e phase and an unknown phase, and they were the dominant intermetallics in as-cast Mg-5Sn-2Ce-xZn alloys. At x=0 wt.%, the Ce-containing compounds formed in interdendritic regions with the shape of rod. As the Zn content was increased to 2 wt.%, the Ce-containing compounds partly changed from rod-like to sheet-like. However, there were few further changes in the Ce-containing compounds with further increase in Zn content to 4 wt.%. Compared with Mg-5Sn-2Ce alloy, the tensile strength and elongation of the alloy containing 4 wt.% Zn increased by 39% and 112%, respectively, and the secondary creep rate（175 °C/55 MPa） decreased at least by an order of magnitude. These improvement could be attributed to the combined effects of the high content of Zn dissolving in a-Mg matrix and the modification of Ce-containing compounds by Zn addition.
