Influence of alloyed chromium on the atmospheric corrosion resistance of weathering steels

The influence of alloyed chromium on atmospheric corrosion resistance (ACR) of weathering steels in simulated industrial atmosphere was investigated. The ACR of weathering steels was evaluated by determining the relative corrosion rate after periodic immersion wet/dry cyclic corrosion for 72 h. The presence of Cr improves the ACR of weathering steels. The beneficial effect of alloyed chromium is attributed to both its promotion of the formation of a protective rust layer, which acts as a barrier against corrosion process, and its enhancement of passivation capability, which decreases the anodic dissolution of substrate alloys.