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Hexavalent to Trivalent conversion for Topcoat sealer

 

I am looking for an alternative solution to plating on automotive liftgate latch components. We currently use a zinc base coat and a dichromate sealer. With the coming of   hexavalent chormate will no longer be an option. We are finding that some colours are no longer an option and this will create issues with materials. So,

1)Are there any other alternative platings at a similar or lower price which provide comparable protection?
2) Is it only our platers which have issues with colour.

Are other platers out there still providing the range of colours in Trivalent which are available now in hexavalent.

Stephen Mitchell
- concord, ontario, canada

The two main problems we have found with changing from hex to tri-chrome are cost and color. If trivalent chrome technology performed just as good, and cost the same or cheaper, then we would never used hex chrome in the first place. Unfortunately, everyone is looking at an increase in cost for plating as a result of new environmental standards.

Also, the technology is new, and trivalent chrome in different colors is still very hard to do without using dyes. You CAN get your yellows, blacks, and olive drabs with trivalent chrome, but you would need to use a dye. Dyes are a nightmare for manufacturing to deal with (which adds cost from down-time and higher rejects). They also fade. As an automotive supplier, I would always recommend clear trivalent with no dye to my customer.

But, it is not just you who has noticed these two issues. Everyone is trying to deal with them. I also want to point out a technical session at the SAE World Congress at noon on March 6th. This will be a panel discussion with OEM representatives about hexavalent chrome issues like this.

Tim Neveau
Rochester Hills, Michigan