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        | Title: | CHEMICAL CONVERSION COATINGSON ALUMINUM AND ALUMINUM ALLOYS | 
      
        | Number: | MIL-DTL-5541 | 
      
        | Revision: | F | 
      
        | Scope: | This specification covers chemical conversion coatings formed by the reaction of chemical conversion materials with the surfaces of aluminum and aluminum alloys. | 
      
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              | Classification: |  |  
                | Types                | The chemical conversion coatings are of the following types |  
                | Classes              | The materials, which form protective coatings by chemical reaction with aluminum and aluminum alloys, are of the following classes. |  | 
      
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              | Details | Description | Can Do |  
                | Type I | Compositions containing hexavalent chromium | Yes |  
                | Type II | Compositions containing no hexavalent chromium | Yes |  
                | Class 1A | For maximum protection against corrosion, painted or unpainted. | Yes |  
                | Class 3 | For protection against corrosion where low electrical resistance is required. | Yes |  | 
      
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