Effect of Environment Control on Phosphating Quality of Cold -Rolled Steels

摘要

Surface condition of cold-rolled steels would highly affect the phosphating quality pre-treated in vehicle cosmetic processes. To promote the phosphating properties, substrate should be maintained as iron fresh or oxidation free. The phosphating reaction of cold-rolled steels occurred by dissolution to ferric ion initially and reacted with solution followed by re-coating on dissolved surface. To improve the cold-rolled steels surface condition, the environment control, such as reduction environment protection by mixed HN gas or surface drying by baking process, was used to restrain oxidation factors reacting with cold-rolled steel surface in this study.