A Two-Stage Conversion Process For Az31B Corrosion

Permanganate phosphate coating is considered as one of the most promising alternative coatings to chromate conversion coating because of the similarity between permanganate and chromate. However, the permanganate phosphate coating always has net-work cracks. In this paper, a thick and crack-free permanganate phosphate coating was developed by a two-stage conversion process. Results of scanning electron microscope (SEM) with X-ray diffraction …