Copper breakdown in liguid aluminium in copper crucible
Copper breakdown in liguid aluminium in copper crucible
(OP)
I am doing experiments with liquid aluminium around its melting temperature in a special copper container with 5mm thick walls.
Heating by inconnel immersion heaters.
A while after aluminium melted, copper walls broke down and aluminium poured out.
Could not see this when it happened because apparatus was encased in insulation. After cooling the copper container appeared to have been eaten away in one side rather than melted. No evidence of pooled copper.
Temperature should not have gone above 670c.
What could have happend since melting point of copper is over 1000C well above experimental temperature?
Thanks





RE: Copper breakdown in liguid aluminium in copper crucible
RE: Copper breakdown in liguid aluminium in copper crucible
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"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year
RE: Copper breakdown in liguid aluminium in copper crucible
A little research or testing could have saved a considerable amount of effort and money. Unfortunately I work with people with a "just do attitude".
I wanted Cu because of its high thermal conductivity. Cant think of a ceramic to match it.
Perhaps a lining of ceramic would prevent interaction but it would have to be thin not to compromise thermal transfer.
RE: Copper breakdown in liguid aluminium in copper crucible
http://www.anceram.com/pdf/aln_artikel_bull.pdf
RE: Copper breakdown in liguid aluminium in copper crucible
I would have assumed Cu would not have gone into solution with Al until its liquidus temperature 1080c were exceeded.
Is there a temperature above 550c when this may be true?
RE: Copper breakdown in liguid aluminium in copper crucible
RE: Copper breakdown in liguid aluminium in copper crucible
_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year
RE: Copper breakdown in liguid aluminium in copper crucible
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
RE: Copper breakdown in liguid aluminium in copper crucible
No, that's the whole point of having to create eutectic phase diagrams, below is the Al-Fe diagram: h
Solder is a common eutectic, where the specific composition 62/38 results in the lowest melting point, which is considerably lower than that of lead. http:
This site has Al-Cu and Al-Si diagrams: http
Again, note that the Al-Si eutectic dips below 600°C, even though Si by itself has a melting point over 1400°C
TTFN

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