Effect Of La、Ce Mixed Rare Earth And Zr Element On Microstructure And Properties Of Commercial Pure Aluminum

Aluminum wire has the advantages of low density,high conductivity,high strength and low cost,and is a key material applied in the field of power engineering.With the rapid development of China’s national economy,the rapid deepening of rural urbanization process,the expansion of power supply users and the diversification of power supply equipment,it is urgent to improve the transmission capacity of aluminum wire and develop large capacity transmission lines.Therefore,the development of high conductivity,high strength aluminum wire to meet the needs of industrial production has important practical significance.Compared with the traditional alloy strengthening method,microalloying can improve the strength of aluminum wire without sacrificing too much conductivity,which is an effective method to effectively improve the comprehensive performance of aluminum wire,and has become a research hotspot in recent years.In this paper,rare earth aluminum alloy and heat resistant aluminum alloy with different compositions were obtained by adding trace La,Ce mixed rare earth and Zr elements separately and La,Ce and Zr elements in the industrial pure aluminum.By optical microscope（OM）,scanning electron microscopy（SEM）,energy spectrometer（EDS）and electron back scattering diffraction test results with electron backscattered diffraction（EBSD）,multifunction electronic tensile machine and QJ-36 arms bridge dc tester and other testing means testing the microstructure and properties of alloy,and the microstructure and mechanical properties of influencing factors were studied in order to provide reliable data support for the further engineering application of this series of alloys.The microstructure of the alloy can be effectively refined by adding La,Ce mixed rare earth into pure aluminum.The alloy is mainly composed ofα-Al matrix and Al-Fe-Si-RE phase when rare earth elements are added in small amounts.Al RE₃phase can be observed to precipitate with the increase of rare earth elements.When the content of RE is higher than 0.3wt.%,the texture strength of{100}plane decreases obviously,and the formation of<100>∥ED and Cube texture is inhibited effectively.When the content of rare earth is 0.2wt.%,the conductivity is the highest,while when the content of rare earth is 0.5wt.%,the tensile property is the best.With the addition of Zr into pure aluminum,the microstructure refinement effect is significant when Zr content is low,and the refinement effect declines and the coarse Al₃Zr phase appears with the increase of Zr content.When Zr content is 0.1wt.%,the texture of{100}plane is the weakest,and the Cube texture is the strongest.When Zr content is 0.05wt.%,the alloy has the highest conductivity and heat resistance.When La and Ce are added to Al-0.05Zr alloy,the effect of rare earth elements on microstructure refinement is not obvious.When the rare earth content is 0.5wt.%,the texture strength of{100}plane is the weakest,and the tensile strength of the alloy is the highest.The conductivity of the alloy increases first and then decreases with the increase of rare earth content.