Chromate Conversion Coatings

Our chromate conversion process can handle parts as small as 1/4" and as large as 3' x 5'. This process is intended for use with aluminum alloys. We offer both trivalent and hexavalent chromate processes in accordance with MIL-DTL-5541F. For trivalent chromate, we can supply a certificate of ROHS compliance.

Facts about chromating:

• Chromate conversion coatings offer excellent corrosion protection, mainly due to the chromium contained in the surface layer. Even after localized damage to the surface film (e.g. scratching or abrading), the surface retains most of its protection, as the chemistry of chromium containing films provides for agradual "self-healing" effect. Chromate coatings are particularly suitable for protecting metal in high-humidity conditions such as those in marine environments.
• A wide range of surface colorings may be obtained by the chromate conversion process. The thinnest chromate layers are typically clear and bright or they may have a bluish tint. Next in order of increasing thickness come the iridescent yellow, brown, bronze, olive drab, and black colors of chromate.
• The texture and fineness of the metal surface produced by preceding operations (e.g. machining, buffing, polishing, etching), may also affect the apparent color of the finished surface.
• Chromate conversion coatings are a good choice for not only significantly enhancing the the initial adhesion of paints, lacquers, and other organic finishes, but also for inhibiting any future loss of adhesion that could otherwise be caused by the undercoating corrosion.
• *Please discuss with our technical representatives your specific requirements related to the final decorative appearance of chromate parts.
• Articles that are protected by a chromate film have generally lower contact resistance than those that are unprotected.
• Chromate coatings are softer than anodized surfaces. While they will withstand considerable handling, stamping and cold forming, they will not withstand continued scratching or hard abrasion.
• Chromate coating thickness varies from 0.000005" to no more than 0.00005".