Cadmium plating in accordance with QQ-P-416, AMS-QQ-P-416, ASTM B766
Cadmium plating (or “cad plating”) offers technical advantages such as excellent corrosion resistance at relatively low thickness and in highly corrosive environments (ie. where excessive salt is used). This finish provides galvanic compatibility with aluminum, reliable torqueing of plated threads, and can be applied as a clear coat or dyed to many colours. It has good lubricity and solderability, and works well either as a final finish or as a paint base. QQ-P-416 Type I gets no post plate treatment. QQ-P-416 Type II gets a post-plate chromate conversion treatment. QQ-P-416 Type III gets a post-plate phosphate treatment. Drawing notes should refer to the type of treatment and thickness class.
With supplementary chromate treatment, drawing notes should clearly specify whether clear, yellow or olive drab as well as the thickness requirements.
Specification | Classification | |
QQ-P-416 / AMS-QQ-P-416 | Types (Supplementary Treatment) | |
I | As plated | |
II | With supplementary chromate treatment (color shall be specified in contract, purchase order or drawing – clear (bluish), yellow or olive drab. | |
Classes (Thickness) | ||
1 | 0.0005 inch minimum | |
2 | 0.0003 inch minimum | |
3 | 0.0002 inch minimum | |
ASTM B766 | Classes (Thickness) | |
25 | 25 microns | |
12 | 12 microns | |
8 | 8 microns | |
5 | 5 microns | |
Types (Supplementary Treatment) | ||
I | As electrodeposited without supplementary treatment. | |
II | With supplementary colored chromate treatment (yellow or olive drab). | |
III | With supplementary colorless chromate . |