Mechanical and Electrical Properties of Y-containing Al-Zr Heat-resistant Alloy Produced by Dynamic ECAE Process

Abstract

The influence of rare earth Y on the microstructure and mechanical properties of Al-Zr alloy produced by dynamic ECAE was studied by OLYMPUS-BX51M optical microscope (OM), S4800 energy disperse spectroscopy (EDS) and SANS CMT5105 electronic universal material testing machine, and the corresponding equivalent conductivity was also investigated by using QJ48 DC electric bridge. The results show that the tensile strength of Al-Zr conductor first increases and then decreases with the increase of the aging time and temperature, and the highest tensile value can be obtained under the aging temperature of 160 °C for 4 h. The ductility and the resistivity of the Al-Zr alloy have inverse proportion to the aging time. The rare earth Y has significantly improved the electrical and mechanical properties of Al-0.3%Zr heat-resistant alloy. In this study, the tensile strength and the elongation of the Al-0.3%Zr-0.2%Y alloy, after aging treatment at 220 °C for 14 h, are about 278.49 MPa and 6.7%, respectively, and the equivalent conductivity is about 59.6 IACS. Hence the synthetical properties of the Y-containing alloy are significantly improved compared with traditional Al-0.3%Zr alloy.

Keywords

Al-Zr heat-resistant alloy / ECAE process / equivalent conductivity / aging treatment

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