Corrosion Behavior of Pure Mg Extrudate

The effect of grain size on corrosion behavior of pure Mg extrudate was evaluated via various method. The pure Mg extrudates with different grain size were prepared by indirect extrusion followed by heat treatment. With increase of average grain size, current density was slightly increased. No obvious feature was not observed on the surface of specimen during cathodic polarization. In the case of specimen with small and homogeneous grain size, corrosion occurred uniformly on the surface of specimen. But in the case of specimen with large and inhomogeneous grain size, corrosion occurred locally. It was concluded that the corrosion behavior of pure Mg extrudate was strongly dependent on grain size and smaller and more homogeneous grain size was more favorable to higher corrosion resistance of pure Mg.