Subject: Re: Stainless steel forging

From: [email-masked] (David Hoopes)
Date: Wed, 31 Jan 1996 06:56:52 -0600

>Stainless steel that has been forged must be heat treated, passivated and
>polished to maintain its stain resistance and strength.  See Carpenter
>Steel Handbook on stainless steels.
>
What does passivated mean?  
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David Hoopes
[email-masked]
Lenexa, Kansas (Near Kansas City, Mo)

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From: Peter Goering <[email-masked]>
Date: Wed, 31 Jan 1996 07:48:57 -0700 (MST)

> What does passivated mean?  
David,
Passivation means there is something "blocking" further reaction i.e., a 
film coating on the metal that stops oxidation. "The corrosion-resisting 
property is due to a thin, adherent, stable chromium oxide or nickel 
oxide film that effectively protects the steel against many corroding 
media." (Avner,1974)  Stainless steel will corrode rather dramatically 
when in contact with chlorine.

FWIW
Pete Goering
Flamingo Forge
Polvadera NM 87828

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From: "Szucs" <[email-masked]>
Date: Wed, 31 Jan 1996 09:48:51 -0500

> What does passivated mean?
	It basically means removal of nickel and iron from the surface
	with nitric acid, exposing chromium, which will then form the
	*passive* oxide layer on the surface which will in turn lend
	the stainless quality to the steel.