View Full Version : nickel silver and stainless


TOM BUCHANAN
02-11-2005, 09:57 PM
as i understand it,ns has a nicke content(18%?) and some stainless does too.i have some stainless that is not magnetic.is this due to a nickel content, and if so whats the difference between the two? thanks for your help guys

mete
02-11-2005, 11:05 PM
Ferromagnetism is found in cobalt , iron and nickel. Nickel silver is a copper alloy with far too little nickel to be magnetic. The stainless steel that is non-magnetic [austenitic] is so IIRC because it has fcc structure austenite rather than ferrite or martensite.

TexasJack
02-12-2005, 01:31 AM
I copied this from somewhere (that I have long since forgotten):

Metallurgically, stainless steels are classified into 3 groups:

Martensitic Class: - This is the straight chromium type of stainless, containing chromium as it's main alloying element. It is normally hard and brittle, includes 4% - 10% Cr, and is air hardening, and magnetic. Examples: 410, 416, 420, 440 series.

Ferritic Class: - Also straight chromium type. Normally is soft and ductile, includes 12% - 28% Cr. It is magnetic. Examples: 409, 430.

Austenitic Class: - Chromium-nickel type. The nickel content usually ranges from 7% - 35%, with 8% - 10% being the most predominantly used. It is strong, ductile and impact resistant. Nonmagnetic in the annealed condition, but slightly magnetic when cold worked. Examples 316, 304.

(Some part of the gray matter says it might have been from Quenchcrack.)

mete
02-12-2005, 06:42 AM
Austenitic -- slightly magnetic when cold worked .Normally the Ms temperature of the austenitic steel is below room temperature therefore it doesn't transform to martensite. There is another temperature the Md temperature which may be above above room temperature .This is where the austenite transforms to martensite when cold worked [Md martensite-deformation] -so sometimes it becomes partially transformed , thus partially magnetic. :101

TOM BUCHANAN
02-13-2005, 12:02 AM
thanks guys...one more question-why is ns so much more expensive than the stainless?

Thingmaker
03-07-2005, 06:32 PM
Because copper is so much more expensive than iron! :)

TexasJack
03-08-2005, 02:02 AM
Probably also has to do with manufacturing. Nickel-Silver is a specialty metal, with limited uses. Stainless steel is made in huge quantities for a wide variety of products ( including the kitchen sink!)