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The opening paragraph of this article says: "Intermetallics are alloys of two or more metals in a certain proportion, thereby forming a new chemical compound (emphasis mine)."

The last sentence of that paragraph cites cementite, or Fe3C, as a commonly used example of an intermetallic. I suggest a different example, or at least an explanation, as this seems to conflict with the opening statement (since carbon is not a metal).

Cheeg 19:11, 29 January 2007 (UTC)

Cheeg suggestion to use an example other than Fe3C is excellent. Why not something like Cu3Au [Ref.: Massalski, T.B., Binary Alloy Phase Diagrams, American Society of Metals, 1986). Cu3Au is an ordered alloy with Cu and Au occupying specific sites within the structure as opposed to a solid solution with random site occupancy.

If Fe3C (cementite) is a solid solution, why does it form a phase boundary with elemental Fe? I would posit that it is, in fact, a distinct crystal structure, in line with XRD & thermodynamic evidence. FYI, Au can dissolve in Cu to some extent, in the same way that there's limited solubility of C in Fe. The fact that C isn't a metal is a point well taken, though, and probably reason enough to change the article. Be bold! --Joel 00:03, 14 February 2007 (UTC)

This is an interesting quandary. I wondered if simply exchanging the word metal for element in the first sentence would do the trick. However and interestingly the result of that is a sentence that clearly tells us that intermetallics are alloys and that seems to be all we were being told originally. It appears that the second paragraph is beginning to explain what an intermetallic really is. How about merging the two paragraphs to bring out the structural composition of intermetallics earlier in the article? Anyone that needs to know what an alloy is can follow the link to that article. Good luck! -- Shropman 11:12, 25 February 2007 (UTC)

I am putting together an article on Zintl phases and came across this article. IMHO it needs much more adding. Intermetallics is a generic phrase covering e.g alloys where Hume Rothery rules apply,interstitials (Hagg phases)-like C in Fe mentioned above, Laves phases and Zintl phases (ionic compounds with e.g. polymeric anions ( the Tl- anion in KTl has a diamond structure) - is anyone out there working on this because I would ideally like to link the Zintl phases article back to this one Axiosaurus 10:52, 7 March 2007 (UTC)

Major revision[edit]

I have made a major revision of this article to clarify the definition(s) of the term. I have removed the contradiction tag, it was not so much a problem of the article but of the way terms alloy, intermetallic & interstitial are used. As far as common usage goes cementite is taught as being an intermetallic by some universities so i guess the confusion will remain. (I was tempted to reference one but I thought better of it.) Axiosaurus 17:02, 14 June 2007 (UTC)

Shouldnt the whole "common usage" section require a citation? There are lots of terms that lots of people commonly misuse, should wikipedia catalog such things? If cementite is commonly called an intermetallic shouldn't that be mentioned on the cementite page, where it is identified (IMO correctly) as a ceramic. (talk) 17:46, 28 April 2011 (UTC)