Research Progress on Surface State and Element Diffusion Mechanism of Steel with Surface Coating Prepared by Pack Aluminizing Method

As fundamental structural materials, steels are widely applied in the national economical fields. Since the oxidation and corrosion occur at steels in engineering applications frequently, surface modification on steel through pack aluminizing can contribute to improve their oxidation resistance and corrosion performance. So far, the effect of aluminizing parameters on the microstructure of coatings, surface integrity and mechanisms for element diffusion is relatively dispersed, which is also deficient and need to be sum up systematically. Accordingly, the impact of aluminizing parameters on the microstructure, surface state and properties of pack aluminized steel was reviewed, and the relationship between aluminizing process parameters and microstructure of the layer was analyzed. In addition, the influence rules of aluminizing process parameters on diffusion coefficient and diffusion activation energy of Fe-Al element were summarized. Also, element diffusion mechanism of Fe-Al and the diffusion mechanism of Fe-Al element was analyzed. The prediction models of aluminized layer is summarized and the tendency of research for aluminized steel prepared via pack cementation has been forecasted.

Automated summary

This study reviewed the impact of pack aluminizing on the oxidation resistance and corrosion performance of steel, analyzed the influence of aluminizing parameters on the microstructure, and summarized the rules of diffusion coefficient and diffusion activation energy of Fe-Al element. Additionally, the diffusion mechanism of Fe-Al element and prediction models of aluminized layer were discussed.