Specifications: MIL-A-8625 Type III, Class 1 & 2 • AMS 2468 and AMS 2469
Hardcoat Anodization is also referred to as Type III Anodizing. Taber abrasion testing shows Pioneer Metal Finishing's hardcoat anodizing exceeds wear characteristics of other hard coatings such as electroless nickel, hardchrome, and ceramic. The Pioneer hardcoat anodizing process produces superior hardness and denseness. When a part is hardcoated, it increases the micro finish 2-5 times, depending on the alloy.
Unmatched wear properties of hardcoating:
• Coatings wear as well as or better than hardened steels (HRC values of 70) as judged by
Suga and Taber Wear tests.
• Can achieve salt spray resistance in excess of 1000 hours.
• Good for salvage work of parts with critical dimensional specifications.
• Can achieve very tight tolerances.
• High dielectric strength to 2000VDC.
• Heat dissipation
Some industrial applications of Hardcoat anodizing include highly intricate parts such as pistons (to view the PDF on high-speed anodizing for pistons click on the resource link to the right), anti-lock brake assemblies, pump components, valves, sliding parts, insulation plates and transmission parts. Some retail applications for Hardcoat anodizing and Sulfuric anodizing include cookware, bike rims, locks and levels.
SALVAGE THROUGH HARDCOATING
The use of hardcoat for salvage operations has proven very successful. Parts rejected because of bores that have been machined oversized are being hardcoated and honed to become acceptable parts. Wrought and cast alloys both lend themselves to salvage operations, but the hardcoat thickness that can be applied is governed by the alloy of the salvage part. Salvage through hardcoat pays off. A prime example is in the aircraft industry, where parts costing thousands of dollars to machine are being salvaged by hardcoating the oversized bores.
ALLOYS AND CASTINGS: THE EFFECTS ON HARDCOAT ANODIZING PROCESSES
The final appearance of a hardcoated surface depends on the alloy and thickness of the coating. The color of an undyed finish can range from gray to black and various shades of bronze can be produced. If close tolerances aren't a factor, Bright Dip will improve the appearance of the finish.
Over 200 aluminum alloys (to view the PDF on alloy specifications click on the resource link to the right), each with up to eight different tempers or hardness values, are available. Each alloy and temper displays unique characteristics with respect to anodic films that can be formed.
