Difference between revisions of "Upgrade/RFFoil/WoodsMetal"

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Wood's metal is an allay with a low melting point, about 60 degrees C. A lot of information on Woods metal can just be found on WikiPedia:
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Wood's metal is an alloy with a low melting point, about 60 degrees C. A lot of information on Woods metal can just be found on WikiPedia:
  
 
http://en.wikipedia.org/wiki/Wood%27s_metal
 
http://en.wikipedia.org/wiki/Wood%27s_metal
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== How to decide on what to use? ==
 
== How to decide on what to use? ==
  
Cerrolow 136 is about half the price of Field's metal.
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Cerrolow 136 (58 �C, 8.5 kg/l, 1.7kEuro/liter) is about half the price of Field's metal (62 �C, 7.88 kg/l, 3.4kEuro/liter).
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What do we need to look at to decide which one we use?
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* shrinkage expansion after solidification: Clow136 skrinks 2x10-4. For a thickness of 2mm, that is less than 1 micron, so probably irrelvant. For Field's metal, we don't know.
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* expansion coefficient? Both should be very close to Al (22-23x10^-6/�C).
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* melting temperature/conductivity? (how warm could foil become while machining?)
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* fluidity: how easily does it flow? does it have sufficient capillary action to make a good film between foil and mold?
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* Al affinity: does it stick well to the Al during milling in its solid phase? can we easily get it off again in its liquid phase?
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* recoverability: stuff is rather expensive (count 5 liter for final box?). how well can we recover it?
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* toxity: Field's metal does not contain lead and less bismuth

Latest revision as of 09:32, 23 October 2014