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How to tell chrome from stainless steel?

  1. Mar 23, 2010 #1
    Dear Experts, :smile:

    Sorry if this post is created in the wrong forum.

    I am not sure how to tell if a metal is chrome plated or stainless steel.
    Is there a simple way to tell?

    Thank you for reading.

    sincerely
    Ramone
     
  2. jcsd
  3. Mar 23, 2010 #2

    mgb_phys

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    Hit it with a hammer - chrome falls off
     
  4. Mar 23, 2010 #3
    You could also compare its density to one of the metals.
     
  5. Mar 23, 2010 #4

    Q_Goest

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    Chrome is highly polished and smooth to a mirror finish. Stainless is slightly dull in comparison and if machined, will show machining marks in the surface. Austenitic stainless is also non-magnetic. Chrome isn't magnetic but the metal substrate generally is.
     
  6. Mar 23, 2010 #5

    DaveC426913

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    This is a test used on barbeques to determine if it's really SS or merely plated steel.

    Steel is magnetic; SS is not.
     
  7. Mar 24, 2010 #6

    Lok

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    Chrome is passive to most chemical corrosives or agents, Cu So4 being a good one to tell steel from chrome, as steel reacts and deposits copper on the surface.

    Stainless does not react though. So the magnetic test should be used for SS and Chromeplating. As said above Stainless isn't magnetic.

    If scrached Chrome plating will reveal a thin layer of copper that is usually needed for better adhesion.

    Chrome is usually of mirror polish, can be rough, and has a light color.
    Steel and Stainless is very light blueish (hard to see), is more matte as it cannot reflect light as good as chorme.
     
  8. Mar 24, 2010 #7

    Q_Goest

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    Just a clarification, it's only (fully annealed) austenitic stainless steels that aren't magnetic.
    http://www.mceproducts.com/knowledge-base/article/article-dtl.asp?id=18 [Broken]
     
    Last edited by a moderator: May 4, 2017
  9. Mar 24, 2010 #8

    turbo

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    Chrome incredibly expensive. If a surface is chrome-plated, it generally has a magnetic substrate. Nothing very large is solid chrome.

    Reminds me of the old Retief and the Warlords series, in which minor dignitaries on far-off planets had desks made of solid rhodium, etc. Keith Laumer was a very tongue-in-cheek writer, but entertaining as hell.
     
  10. Mar 25, 2010 #9

    Lok

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    Most stainless found is austenitic as it is alloyed with nichel.
    Ferritic is alloyed with chrome, and therefore expnsive.
    Martensitic and self hardening is with Manganese.

    All of the above are exemples and not the only variants, V W Cr Co Mn Ni Al, and a lot more can get into alloys, with different properties.
     
    Last edited by a moderator: May 4, 2017
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