Effect of Er on Microstructure, Electrical Conductivity, Mechanical Properties, and Corrosion Resistance of an Al-Zr Alloy

The influence of the rare earth element Er on the microstructure, electrical conductivity, mechanical properties, and corrosion resistance of an Al-Zr alloy was studied. The results presented that adding Er element to Al-Zr alloy is beneficial to refine the grains. As the content of Er element increased, the fraction of second phases in the Al-0.08Zr alloy gradually increased. The solution of silicon and iron impurities in Al matrix decreased with the Er addition. The addition of Er lead to the electrical conductivity and strength of the Al-0.08Zr alloys increased. The electrical conductivity reached 63.01% IACS of Al-0.08Zr-0.16Er alloy, which promoted by 2.94% compared with that of Al-0.08Zr alloy. The Al-0.08Zr-0.16Er alloy presented ultimate tensile strength of 78.09 MPa and yield strength of 59.18 MPa, which are both 27.85% and 42.16% higher than those of Al-0.08Zr alloy. The adding of Er element in the Al-0.08Zr alloy resulted in the improvement of corrosion resistance.