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        | Title: | COATING, ELECTROLESS NICKELREQUIREMENTS FOR | 
      
        | Number: | MIL-C-26074 | 
      
        | Revision: | E notice 3 | 
      
        | Scope: | This specification covers the requirements for electroless (autocatalytic chemical reduction) deposition of nickel-phosphorous alloy coatings on metal and composite surfaces. | 
      
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              | Classification: |  |  
                | Classes              | The nickel coating shall be classified in accordance with the thermal treatment applied subsequent to plating. |  
                | Grades               | The nickel coatings shall be of the following grades. |  | 
      
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              | Details | Description | Can Do |  
                | Class 1 | As plated, no subsequent heat treatment:  A bake for hydrogen embrittlement relief in not considered a heat treatment. | Yes |  
                | Class 2 | Heat treated to obtain required hardness:  May be used on all metals not affected by heating to 500F and above. | Yes |  
                | Class 3 | Aluminum alloys nonheat-treatable, and beryllium alloys processed to improve adhesion of the nickel deposit. | Yes |  
                | Class 4 | Aluminum alloys, heat-treatable, processed to improve adhesion of the nickel deposit. | Yes |  
                | Grade A | 0.0010 inch minimum | Yes |  
                | Grade B | 0.0005 inch minimum thickness | Yes |  
                | Grade C | 0.0015 inch minimum thickness | Yes |  | 
      
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