Chromic acid anodising is a type of anodising that results in a thin oxide layer with optimal adhesion and corrosion resistance. It is electrolytically formed anodic coatings on aluminum and aluminum alloys.
TYPES
Type I – Chromic acid anodizing, conventional coatings (50V) produced from chromic acid bath
Type IB – Chromic acid anodizing, low voltage process, 22 +/- 2V
CLASSES
Class 1 – Undyed (Sealing – Deionised Water, Dichromate, Nickel Acetate)
Class 2 – Dyed (Red, Black, Customized)
CHROMIC ACID ANODIZING -PROCESS CONTROL & TEST METHOD
VISUAL INSPECTION – MIL-A-8625 & CUSTOMER SPECIFICATION
THICKNESS TEST – ASTM B 244
FILM CONTINUITY TEST – MIL-A-8625 & CUSTOMER SPECIFICATION
COATING WEIGHT TEST – ASTM B 137
CORROSION RESISTANCE TEST – ASTM B 117