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TFS(tin-free steel)continuous electroplating

Thread starter fredman
Start date Aug 22, 2002

Status: Not open for further replies.

Aug 22, 2002

fredman

Chemical

I am currently involved in commissioning of a 2-step hexavalent chrome continuous electroplating proccess,which uses CrO3 as a source of chrome,NaF as the catalyst, and in the second step NaOH for pH control to stop re-dissolution of plated metal oxides.Anodes are Pb,5%Sn.What I would like to know is some more specifics(on the atomic level) of the structure of the chrome, and how the catalyst works.Is the catalyst used just to break the bonds on the CrO3?What is the structure of the chrome,and how does is change by electrolysing?