Are you still using the same fastener finish that you did ten years ago? Electroplating, the “gold standard” fastener finish is NOT the same as it was five and ten years ago.
The major change to zinc electroplating over the last ten years is a switch from hexavalent chromium to trivalent which is less toxic to the environment. Some countries and specific industries have regulations banning hexavalent chrome which is forcing platers to change formulas. If you don’t need RoHS or REACH compliant fasteners, odds are your fastener finish has changed without your knowledge.
3 Reasons Why Updated Fastener Finishes Should Be Important to You
- If you’re still buying yellow zinc, you could be paying too much. Hexavalent chrome was yellow by default, but trivalent is clear colored. If you are getting yellow trivalent, you are paying to have a dye added to the finish which may not be necessary.
- Your corrosion protection may be less than expected. Trivalent chromate is not “self-healing” like hexavalent. This could lead to premature white corrosion products and dissatisfied customers.
- The coefficient of friction is different between hexavalent and trivalent chrome which could cause problems during assembly with stretching and breaking bolts using the same torque as you have always used.
What Are Alternative Finishes to the Standard Electroplated Zinc?
- Electroplated zinc nickel can offer much higher corrosion protection, and lower your risk of hydrogen embrittlement (HE) on high strength fasteners
- Zinc flake coating offers high corrosion protection, no HE risk and a controlled CoF to ensure more consistent joint clamp load
- Phosphate coatings offer good shelf life protection from corrosion and provide a good base for paint
- Epoxy electrocoat finishes offer a very nice uniform black cosmetic finish while providing good corrosion protection and no HE risk
Bossard offers Expert Education seminars as webinars or in person at your facility, tailored to your specific questions and needs. For a full seminar on Plating and Coatings, contact us at ProvenProductivity@bossard.com.
Doug Jones
Applications Engineer
djones@bossard.com
