four questions for you steve
1) what the hell do you do for a living?
2) what is a binary phase diagram?
3) at the eutectic temerature with the right eutectic composition are there
two different metals present?
4) why did most of that make sense?
derek
Answers:
1: I am a technical manager (metallurgical engineer) for a foundry/machine shop.
2: A binary phase diagram is like a "map" of how metal systems behave at differing compositions and temperatures. Across the X axis is composition - at one end of the Al-Si phase diagram is pure Aluminum. At the other end of the axis is pure Silicon. The midpoint is 50% Al, 50% Si. On the Y axis is temperature. There are many phases present on such a phase diagram, depending on composition and temperature. These phases are defined by their crystal structure. Phase diagrams can be found for most metal systems in foundry and engineering handbooks, etc.
3: Aluminum and Silicon are metallic elements. That means yes, there are two metals present. However, above the eutectic line on the phase diagram, the Al and Si combine to make one distinct phase. Below the eutectic line, two distinct phases are formed, with differing crystal structures. (I don't have the Al-Si diagram in front of me right now, so I'm not sure what the structure of these two phases are).
4: It makes sense because it is science. There is no black magic involved, just simple facts and metallurgy.
Thanks for the comments and questions.
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