Corrosion of Fe–B–Si alloys in liquid zinc

Abstract

The influence of the Si content and corrosion temperature on the formation of the compact multiphase corrosion-product layer when Fe–B–Si alloys were corroded in liquid zinc, was studied. Si was enriched at the corrosion interface and dissolved in the corrosion product layer, thus, affecting the diffusion of Zn and Fe. The multiphase corrosion product layer composed of Fe–Zn compounds with residual Fe2B at the corrosion interface was formed. The Fe–Zn compounds are tightly occluded among the residual Fe2B phase, which can inhibit diffusion. The Fe–Zn compounds tend to dissolve at high temperatures. However, because the complete residual Fe2B skeleton structure was retained and a small number of compounds remained among the residual Fe2B skeletons, the inhibition of the multiphase corrosion product layer did not cease. When the Si content was 0.318 wt%, the corrosion product layer was the densest, and when the Si content was 0.196 wt%, the corrosion product layer had the weakest diffusion-inhibition effect.