This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Development of Simultaneous Zinc Phosphating Process for Aluminum and Steel Plates
Annotation ability available
Sector:
Language:
English
Abstract
A method was studied for simultaneous zinc phosphating on aluminum and steel surfaces to obtain high corrosion resistance on aluminum surfaces, which conventional phosphatic processing could not provide with sufficient corrosion resistance.
Since aluminum is protected by an oxide film on its surface, it has poor processability with zinc phosphating solutions applied to steel. An appropriate quantity of fluoride was therefore added to improve processing, and the coating film, aluminum composition and surface conditions were optimized to suppress filiform corrosion, which is characterized by string-like blisters of paint film starting from a paint defect.
In addition, in view of the actual production environment, the corrosion resistance of the ground area made for readjustment after stamping was studied for the optimization of the processing solution.
As a result of this study, zinc phosphating of aluminum and steel in the same bath is currently done in actual production operations, and the resistance of processed aluminum to filiform corrosion proved higher than when chromic chromating was applied.
Authors
Citation
Miyazaki, N., Nakatsukasa, M., and Okazaki, K., "Development of Simultaneous Zinc Phosphating Process for Aluminum and Steel Plates," SAE Technical Paper 931936, 1993, https://doi.org/10.4271/931936.Also In
References
- Komatsu Y. et al Joworal of the Soc. of Automotive Engineer of Japan 45 6 1991 42 48
- Automotive Technologies 45 6 49 54 1991 Komatsu Y. et al.
- Surface Technologies 43 550 1992 Matsumoto T. Nishino T.