Effect of nano Al (Scx−1Zrx) precipitates on the mechanical and corrosion behavior of Al‐2.5 Mg alloys

Abstract

AbstractMicroanalytical, mechanical, and corrosion studies were undertaken to investigate the effect of nano‐precipitates of Al(Scx−1Zrx) on the mechanical and corrosion characteristics of Al 2.5 alloy containing 0, 0.15, 0.3, 0.6, and 0.9 wt% of Sc with 0.15 wt% Zr. Addition of 0.3% Sc significantly increased the yield strength due to small precipitates sizes (5–19 nm) and the high coherency of the nano‐particles. Largest contributor to the strength was grain boundary strengthening caused by pinning of grain boundary precipitates. The alloys showed a good resistance to corrosion in 3.5 wt% neutral chloride solution. The alloy offered a high passivation tendency because of homogeneous coherent nano Al(Scx−1Zrx) precipitates. The nano precipitates interfaces and homogeneously distributed Al3Sc precipitates offer a high degree of corrosion resistance to Al 2.5 Mg Sc alloys compared to conventional aluminum alloys, such as Al 6061 and Al6013.