Corrosion Prevention for External Magnesium Automotive Components

Anodizing Treatments for Magnesium Alloys and Their Effect on Corrosion Resistance in Various Environments

“…14). [92] Salt spray and atmospheric exposure tests on die cast AZ91D undergoing different surface treatments and atmospheric galvanic corrosion of AZ91D coupled to dissimilar metals clarified the following points: [94] Even after 4,000 hrs of continuous 5 % NaCl solution spray and 3-year atmospheric exposure test, no defects such as blisters or corrosion was observed on the coated surfaces. This indicated good corrosion resistance, equivalent in appearance to that of coated die cast aluminium alloy ADC12.…”

“…[49] However, in comparison to sealed Anomag the performance of sealed Magoxide-Coat was found to be slightly worse. [92] It is important to state that even the relatively weak performing coatings, such as HAE, if sealed in a proper way, are able to provide years of service without problems, for example in aircraft applications. [93] The corrosion protection performance of selected anodized coatings on magnesium has been compared to that of traditional chromate conversion coating and vibratory finishing.…”

“…Average rating was reported for scribe and non-scribed areas. Details about the test method and the rating system are given by Wang et al (2001). [92] The performance of these anodizing coatings was better than that of chromate treatment.…”

“…Details about the test method and the rating system are given by Wang et al (2001). [92] The performance of these anodizing coatings was better than that of chromate treatment. The best corrosion protection could be achieved by an Anomag/sealant system, followed by Magoxid/sealant and Cr-free passivation treatments.…”

Environmentally Friendly Composite Film of Anodizing and Electrodeposition Coating Having a High Corrosion Resistance on Magnesium Alloy AZ91D

“…Therefore, we consider the optimum treatment method to be the composite treatment of anodizing for over 10 mm of economical passive film, in place of conventional thin film chemical conversion as a substrate treatment, and on it, apply electrodeposition coating which is economical and has good covering power. [7][8][9][10] In our previous paper, 11) as an environmental measure, we reported an environmentally friendly and excellent corrosion resistant SAF which did not contain any hazardous substances, unlike DAF and CCF containing hexavalent chromium as well as fluorine and phosphorus compounds.…”