Effect of Ni Content on Atmospheric Corrosion of Low Alloy Steels

Effect of Ni content on atmospheric corrosion in the regions of Qingdao and Jiangjin for low alloy steels was investigated.The results show that the steel with 2.68% Ni exhibited better corrosion resistance under the conditions with S and/or Cl-,the resistance to Cl- corrosion was better than that to S corrosion.The XRD analyses show that there were more δ-FeOOH and α-FeOOH and less β-FeOOH in the rust of the steel with 2.68% Ni than that of the carbon steel exposed for 24 months ,indicating that the rust layer for the steel with 2.68% Ni was denser in the atmosphere with Cl- and could impede the permeating of Cl-.