Effect of Sc and Zr additions on the microstructure and fatigue properties of AA6106 produced by equal-channel-angular-pressing

The effect of Zr and Sc addition on the grain refinement and mechanical properties of 6106 aluminium alloy produced by equal-channel-angular-pressing (ECAP) have been analyzed in the present study and compared to the polycrystalline conditions. The concomitant effect of both Zr, Zr + Sc, and precipitation hardening secondary phases, and the severe plastic deformation of the commercial alloy was found to increase the tensile strength and high cycle fatigue limit. The fatigue crack growth tests revealed a reduction of crack initiation but a faster crack growth after ECAP.