
plating, anodizing, & finishing Q&As since 1989
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Need economical coating/plating to pass 1000 hour salt spray test
May 29, 2010
Hello,
I hope you can help me out. I have high quantity of steel plates and weldments that I need a coating or plating that would pass a 1000 hour salt spray test. The coating or plating needs to be fairly cheap. Looks after plating or coating is not important at all. The other requirement is it has to be blue in color, shade of blue doesn't matter. There are 60000 pieces around 1/2" x 5" x 5" in size. The weldment is 2" x 2" x 1/8" wall steel tubing around 3 feet long. There is also around 60000 of these also. Any advice on what to look for or who can do this would be greatly appreciated. Thanks in advance.
Job Shop - Deptford, New Jersey, USA
June 2, 2010
Hi, Steve. A good quality epoxy or polyester powder coating after a good pretreatment should be able to go a thousand hours, but you may need more weld preparation than you would prefer, and you may require an electrophoretic primer first. Galvanizing sounds like another good answer, with exceptional real-life performance, but salt-spray testing of galvanizing is problematic because it's actual corrosion resistance is dependent upon the formation of intermediates that don't form in a salt spray test chamber.
Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 9, 2010
Hi Steve Boyle,
Better try with Nylon based Powder coating, it is available in blue color.
- Salem, Tamil Nadu, India
