Expert: Lee Gearhart - 12/21/2000

Question
what is Iron Ferrite, what is it used for, and where is it found  

Answer
Hello Philip!
Well, there are a few definitions that match your question.  First, "ferrite" is the name metallurgists give to the body-centered-cubic phase of iron and it's alloys.  The 'body-centered-cubic' phrase refers to the way the atoms are arranged in the lattice, to distinguish it from "austenite" which is the face-centered-cubic arrangement.  Generally, ferrite is a pretty pure iron- the core iron used in electrical transformers, for example, is ferritic-but there are also some stainless steels that are ferritic.  These iron-chromium alloys would have 12 to 18% chromium in them, and are used for expensive exhaust systems in automobiles, for example.  Iron is not found in nature, as are, say, chunks of copper, but must be refined by a blast furnace or other smelting technique.

Then again, your question could relate to magnetic ferrite, which has the general formula MOFe2O3,  where M means some divalent metal ion  (Cr, Cu, Mn, Ni, etc).  There are both soft and hard ferrites, which refers to their magnetic properties: whether they easily magnetize and demagnetize or not.  The soft ones are used in RF (radio frequency) electronics, while the soft ones are used in speakers for small headphones, for example.  Ferrites are also manufactured- not found in nature, except for the mineral Magnetite.

I hope this answers your question!

Lee Gearhart