Influence of hot rolling on the corrosion behavior of several Mg-X alloys

The influence of hot rolling on the corrosion of Mg-X alloys (X = Gd, Ca, Al, Mn, Sn, Sr, Nd, La, Ce, Zr or Si) was investigated by immersion tests in 3.5% NaCl solution saturated with Mg(OH)2. The corrosion rates for all Mg-X alloys (except Mg0.1Zr and Mg0.3Si) decreased after hot rolling, attributed to fine-grained alloys having a more homogeneous microstructure, and fewer, smaller second-phase particles. For Mg0.1Zr and Mg0.3Si, the corrosion rate increased after hot rolling. There were a number of possible reasons, one of which was a greater sensitivity to the precipitation of deleterious Fe-rich particles.