Mechanical and Electrical Properties of Al-Fe-Cr and Al-Fe-Zr Alloys

The effect of aging on the strength and conductivity of cold-rolled and fully-annealed Al-Fe-Cr and Al-Fe-Zr alloys were studied. The strength of the Al-Fe-Cr and Al-Fe-Zr alloys increased to 158 MPa and 150 MPa, respectively, with aging at 180 degrees C at the minimal expense of ductility. The stress-strain responses showed a softening behavior even after aging, suggesting that the cold-worked microstructure obtained via cold-rolling was not softened by aging at 180 degrees C. The optimum strength/conductivity obtained for the aged Al-Fe-Cr was 158 MPa/51% IACS, and the increase in electrical conductivity is accompanied by an increase in strength, which indicates that precipitation is mainly responsible for the increase in conductivity. A higher value of conductivity in the cold-rolled and aged alloys than in the fully annealed and aged counterparts implies that the gain in the conductivity due to precipitation is greater than the gain in conductivity due to the decrease of dislocation density was about 0.017.