Chemical Solutions
Chromating
Chromate conversion coatings react with the aluminum surface and form a thin barrier coating that inhibits corrosion. Hexavalent chromates that provide a yellow iridescent finish are being replaced with more environmentally friendly trivalent chrome formulations like CHEMEON TCP-HF (Hex Free) that produce a clear to slightly iridescent finish. Selecting the correct chromate conversion coating depends on the following:
- Military or Aerospace Specification – many still call out for hexavalent yellow chromate conversion coatings
- Corrosion Resistance – CHEMEON TCP-HF (Hex Free) provides better salt spray hours (over 300) compare to old hex chromates
- Finishing Requirements – CHEMEON TCP-HF (Hex Free) provides an excellent base for painting over aluminum
- Waste Treatment – trivalent chromates are easier to waste treat than hexavalent alternatives
- Color – although the finish is clear CHEMEON TCP-HF (Hex Free) out performs the old yellow hex chromates
Description
CHEMEON TCP-HF (Hex Free) is an environmentally safe and superior trivalent chromate alternative to hexavalent chromates. The Department of Defense and the United States Navy initially developed and tested this product for use in extreme applications. Surpassing over 15,000 test panels CHEMEON TCP-HF (Hex Free) outperforms existing trivalent and hexavalent alternatives in wear and corrosion resistance (without requiring additional topcoats)
CHEMEON TCP-HF (Hex Free) Capabilities
| Process | Trivalent chromium |
| Applications | Chemical conversion coatings. Anodized aluminum sealer. Passivate and anti-tarnish. |
| Industry Specifications and Standards | MIL-DTL-81706. MIL-DTL-5541 Type II. MIL-C-5541 Class 1A and Class 3. ROHS. REACH. WEEE. ELV. OSHA, ASTM B921. QPL. |
| Substrates | Bare aluminum and anodized aluminum. Zinc and zinc alloys. Magnesium. Galvanized steel. IVD. Cadmium. Titanium. Zirconium. |
| Properties | Extended corrosion resistance. Paint adhesion. Electrical properties. Coating durability. |
| Application Methods | Immersion. Spray. |
| Corrosion Resistance | 336h NSS bare aluminum. 3,000h+ anodized aluminum. |
| Temperature Exposure | Can be dried at 250°F Can be baked for hydrogen relief at 250°F for 24+h without loss of performance |
| Product Advantages | Lower solution operating temperature. Harder than conventional hexavalent. Can be applied and dried in bulk. No topcoat required. Extreme temperature exposure – UP TO 450°F. Average coating weight 22.88 mg/ft2. |
| Industries Served | Aerospace. Military/Defense. Automotive. Medical. Cookware. Commercial. Architectural. Marine. Avionics. Electronics. Heavy equipment. |
