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Help - need info on AMS 2433B spec
I have a callout for AMS 2433B Type 2 electroless nickel. I don't have the spec. Can someone help me? I need to know what the type 2 refers to - thickness, phos content, heat treatment?
Thanks
plating co., - Lowell, Massachusetts
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My suggestion is NO QUOTE! AMS2433 [link is to spec at TechStreet] is NOT electroless nickel as most platers know it. It calls specifically for nickel-boron-THALLIUM which is a far cry from the conventional nickel phosphorus electroless nickels as called out in AMS2404 [link is to spec at TechStreet] and AMS-2405 [link is to spec at TechStreet]. Straight nickel-boron is covered by AMS 2399. Most companies won't touch thallium bearing solutions - check out the health concerns associated.... From one websource: "Exposure to high levels of thallium can result in harmful health effects. Studies in people who ingested large amounts of thallium over a short time have reported vomiting, diarrhea, temporary hair loss, and effects on the nervous system, lungs, heart, liver, and kidneys. It has caused death. A study on workers exposed on the job over several years reported nervous system effects, such as numbness of fingers and toes, from breathing thallium."
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Milt Stevenson, Jr. Anoplate Corp  Syracuse, New York |
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Another letter here, 34681, says that although Type 1 contains thallium, Type 2 doesn't, Milt. We should all work from actual copies of the spec, but I don't have one and am not going to buy one for a theoretical discussion. Maybe someone who is looking at it can advise us on that.
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |
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Hello Stephen!
AMS 2433C is the current revision, and it says Type 1 is Nickel Thallium Boron, while Type 2 is Nickel Boron. N-T-B has 2.5 to 5.0% Boron with 2.5 to 6.0% Thallium. The Nickel Boron is 2.5 to 8.5% Boron.
There isn't a change bar next to these paragraphs, so I believe that the B revision says the same thing.
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Lee Gearhart |