The Research Of Er-added Heat-resistant Cond Aluminum

Nine groups of aluminum alloy:Al-0.04Er、Al-0.04Er-0.04Zr Al-0.04Er-0.04Zr-B、Al-0.1E、Al-0.1Er-0.04Zr、Al-0.1Er-0.04Zr-B、Al-0.2Er、 Al-0.2Er-0.04Zr、Al-0.2Er-0.04Zr-B, were fabricated by melting99.85%commercial pure Al, pure Er, Al-4.07Zr and Al-3.11B master alloys in air. All cast alloys were homogenized at560℃for20h. Then all alloys were cold-rolled with the cumulative area reduction of85.7%and hot-rolled. After this, the tensile properties, electrical conductivities and tensile strength remnant ratio tests were measured and tested high temperature creep properties of Al-0.1Er-0.04Zr-B at varied stress loading under200℃. According to the theory of EET, the valence and interface electron structure of each phase were calculated.After hot-rolling and cold-rolling, the tensile properties of each sample was no obvious difference and did not change significantly with the kind and content of the element’s addition.The tensile strength remnant ratio tests show that the tensile strength remnant ratio of almost all alloys reached90%after kept1h under260℃, which is better than the evaluation standard of tensile strength remnant ratio was90%after kept Ih under230℃. The tensile strength remnant ratio of sample Al-0.1Er-Zr was95%, after kept1h under260℃. So it was possible to develop as a super heat-resistant cond aluminum on this basis. High temperature creep properties of Al-0.1Er-0.04Zr-B at varied stress loading under200℃show that threshold stress was30.0327MPa.The relationship of electrical resistance and temperature shows the electrical conductivity of sample Al-0.1Er-Zr-B was the best under20℃. The electric conductivity was61.03%IACS, which fit the stranded to pure Al wire. And it was possible to develop as a super conductive heat-resistant aluminum on this basis. The electrical conductivity of sample Al-0.04Er-Zr-B also fit the stranded of60%IACS. Especially, there was only0.04%Er added, so the price was low. Then it can be developed as high heat-resistant Al alloy. However, under100℃, the electrical conductivity of sample Al-0.1Er was the best, and temperature coefficient of resistance α=0.0032/℃. The resistivity was lower more than3%to other sample. So Al-0.1Er was a kind of very promising thermal conductive metal.The valence electron structure and bond energy of each phase show that the sequence of each phase generating was ZrB2> ErB2> Al3Er> Al3Zr. The interface electron structure of each phase shows that:the electron density difference of interface of both Al3Er and Al3Zr with Al matrix was low. They can be used as heterogeneous nucleation center of Al matrix, and refine the grain size. However, the electron density difference of interface of both ZrB2and ErB2with Al matrix was high; they can not be used as heterogeneous nucleation center of Al matrix, and can not refine the grain size.