51021

Tri-chrome or chrome-free Brass Iridite?  

January 21, 2009

We are using a process of brass iriditing (the product name is 'metcoat') on brass bar stock machined parts to give them a bright, shiny, and salt resistant coating. They go through a "bright dip" before this step. This process involves the use of hexavalent chrome.

I have two questions that I haven't been able to answer by searching the archives:
1) is there a non hex alternative for brass that will provide a similar bright shiny surface. It doesn't truly need to be as durable to salt spray as the hex but at least resist fingerprints and not turn green in normal service
2) is hex chrome banned altogether in China. We are getting reports that this is the case but have been unable to confirm.

Jon Stokes
manufacturer - Elk River, MN, USA

First, I do not believe (quite strongly) that hexavalent chromium is banned in China. It is, however, banned by the EU and by companies who utilize standards (i.e. RoHS) that basically ban the use of heavy metals in certain forms. Secondly, there are seperate non hexchrome products available for bright dipping and for passivating/tarnish protection. You should contact your supplier or others.

Gene Packman
- Great Neck NY