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-----Purpose of Topcoat?
What is the purpose of topcoat in plating process?
Is topcoat influence in increase the SST?
buyer - Bangalore
March 28, 2008
Hi, RS. "Topcoat" could mean different things in different contexts, but maybe you are referring to a topcoat that follows trivalent chromating on zinc and zinc alloy plating processes? Yes, it's purpose is to increase the Salt Spray Time.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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March , 2008
Mr. Sum,
Top-coat, sealer or finigard usually mean the same process of increasing corrosion resistance in SST by sealing passivation layer on zinc deposit. Top-coat is the only real alternative for hexavalent chromium passivation when we want to keep the same level of protection using trivalent chromium. Unfortunately, top-coat is expensive and difficult process, which can significantly change the cost of zinc plating.
- Warsaw, Poland
March 31, 2008
sir,
I am confused regarding ROHS compliance.
is it the only test to confirm that if the material / solution is ROHS compliance, then it has to be non hazardous to nature or human?
or what are the benifits if the solution is ROHS compliance?
please explain...
- India
July 28, 2008
Hi, Sagar
RoHS is an acronym for Reduction of Hazardous Substances. The context is that the European parliament has placed limitations on how much cadmium, mercury, lead, hexavalent chromium and a few other substances are permitted on a wide range of products that will be sold in or used in Europe. If your product doesn't comply, and is within the range of regulated product lines, it can't be shipped there.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Need quick confidential answers? $25
Need project assistance? $100/hr.
July , 2008
Sorry! Finishing.com is temporarily Read-Only.
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