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Comparisons of Chrome Plating Vs. Alloy

A naturally occurring metal found in many foods is the same metal on most wheels and bumpers that gets that extra bit of polishing. Chromium is the sixth most abundant element found in the earth's crust where it combines with oxygen and iron, resulting in chromite ore. Chrome, the common name for chromium, is a lustrous, silver-gray hard metal that is too brittle for any uses by itself, but is beneficial for protecting other metals from oxidation and to provide a brilliant appearance.

Chrome Alloys
- Stainless steel is an alloy that contains chrome, and is used in food and medical environments.
  
  Mixing any two or more metals creates an alloy. Steel, though a very strong metal, easily corrodes when exposed to the elements. When chromium is mixed with steel the result is stainless steel, an alloy with a non-corrosive, non-permeable and shiny surface. Amoz, an online materials database, notes that an 80/20 nickel chromium alloy is often used for wrought and cast parts used for high-temperature applications. This nickel-chrome alloy has high resistance to oxidation and chemical corrosion. Chrome's non-corrosive ability makes chrome alloys a favorite choice for implanted medical devices such as heart stents made from stainless steel and platinum-chrome alloys.
Decorative Chrome Plating
- Chrome plating is used to make metals both attractive and weather resistant, and can be used on other materials.
  
  Items that look like chrome really have very little chrome, not only because the chrome is limited to a surface coating, but what is actually seen is often another metal plating underneath the chrome. Chrome is always applied in an electroplating process. "Decorative chrome plating" is what most people would be familiar with, and is sometimes called "nickel-chrome plating." In this process nickel is first electroplated onto the object by itself, or sometimes after copper has first been electroplated. Nickel is smooth, better protects the underlying metal from corrosion and is highly reflective, even moreso than chrome. In this plating method, chrome is used in a very thin, transparent coating. Chrome's only purpose is to control nickel's yellow undertones, as chrome has a "blueish" reflective quality that creates the appearance of silver.
Industrial Chrome Plating
- Methods of industrial chrome plating protect mechanical parts that are exposed to high heat, moisture or chemicals.
  
  Chrome is used in two additional electroplating methods targeted for industrial use that use more chrome in the process. "Hard chrome plating," sometimes called "engineering chrome plating" is used for industrial purposes with a thicker layer of chrome that is primarily used to protect underlying metals. The newest method, called "selective plating" or "brush plating," may include the electroplating of chrome or chrome alloys.
Bio Safety
- Erin Brockovich is a consumer advocate made famous in the 2000 movie.
  
  The Centers for Disease Control notes that the toxicity of chromium compounds depends on the oxidation state of the metal. Chromite ore is what is called the trivalent state and is often noted as Cr(III). This is the natural, non-toxic state of the chromium element used in the manufacturing of alloys such as stainless steel and is naturally present in foods. However, the chrome used in electroplating is hexavalent chromium, noted as Cr(VI), is extremely toxic and carcinogenic when ingested, inhaled or absorbed through the skin. This is the same chemical Erin Brockovich uncovered in the early 1990s as the 30-year cause of mass health problems in Hinkley, California.

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