Microstructure and properties of novel Al-Ce-Sc, Al-Ce-Y, Al-Ce-Zr and Al-Ce-Sc-Y alloy conductors processed by die casting, hot extrusion and cold drawing. (1st December 2020)

• Record Type: Journal Article
• Authors: Wang, Weiyi; Pan, Qinglin; Lin, Geng; Wang, Xiaoping; Sun, Yuqiao; Wang, Xiangdong; Ye, Ji; Sun, Yuanwei; Yu, Yi; Jiang, Fuqing; Li, Jun; Liu, Yaru
• Is Part Of: Journal of materials science & technology. Volume 58(2020)
• Page Start: 155
• Page End: 170
• Publication Date: 2020-12-01
• Subjects: Al-Ce-Sc-Y alloy -- Electrical conductivity -- Mechanical properties -- Second phase -- Nano-size precipitates; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2020.03.073
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract: In order to overcome the trade-off between the strength and electrical conductivity of aluminum alloy conductors, the new Al-Ce-Sc, Al-Ce-Y, Al-Ce-Zr and Al-Ce-Sc-Y alloys were prepared by die casting, high temperature homogenization treatment, hot extrusion and cold drawing. Adding Sc and Y eliminated the dendrite segregation of the as-cast Al-0.2Ce alloy and promoted the formation of equiaxed grains with the average grain size of 142.5 μm. The Al-0.2Ce-0.2Sc-0.1Y alloy inherited the great tensile properties of Al-0.2Ce-0.2Sc alloy and the high electrical conductivity of Al-0.2Ce-0.1Y alloy simultaneously. After cold drawing and annealing at 200 °C for 5 h, the ultimate tensile strength of Al-0.2Ce-0.2Sc-0.1Y alloy reached 200 MPa and 198 MPa, the elongation reached 6.8 % and 8.5 %, and the electrical conductivity reached 61.01 % and 61.77 %, respectively. The main second phase of Al-0.2Ce-0.2Sc-0.1Y alloy after hot extrusion were Al13 Fe3 Ce containing a few Y and Si atoms. The larger size and proportion of the second phase greatly reduced the concentration of solute Fe and Si atoms and the addition of Y significantly decreased the density of defects after cold drawing compared to Al-0.2Ce-0.2Sc alloy, which improved electrical conductivity of the alloy. Furthermore, the dispersed and coherent nano-size Al3 Sc precipitions of Al-0.2Ce-0.2Sc-0.1Y alloy greatly improved strength, elongation and heat resistance. Compared with Al-0.2Ce-0.2Sc alloy, the lower density of dislocation, stacking fault and subgrain boundary and the larger size of Al3 Sc precipitions with enrichment of Y atoms enable the Al-0.2Ce-0.2Sc-0.1Y alloy to maintain high strength, elongation and electrical conductivity after annealing.