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Hexavalent Substitute

My company manufactures and sells solenoids all over the world. Sizes can range from 2" to 5" in height and 0.75" to 5" in width. The solenoid body is made of 1010, 1020, 12L14, 12L15 steel. We currently are using yellow hexavalent with yellow zinc dichromate. Our major concerns are corrosion protection, cost, and appearance. What would be a good substitute for using yellow hexavalent that would have comparable protection, cost, and appearance? Would changing the process from electrolytic plating to a different plating technique such as electroless, metal spraying, vacuum metallizing, or etc., be beneficial? Thanks in advance for your help :>)

Christopher Kane
Engine Control Systems - Chicago, Illinois, USA
2006

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You are at the point on the curve where this won't be much of a problem anymore, Christopher. Many if not most plating shops have already converted from hexavalent chromates to trivalent. You simply need to rewrite your spec a bit to say that chromating must be trivalent and comply with RoHS and ELV requirements. Think about whether the chromate really needs to be yellow anymore, though, because some of the trivalent formulations are not yellow and it will limit your options if you insist on it. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006