I've started selecting materials to construct a tube furnace. I noticed that garage chemist's tube furnace was constructed using kanthal wire instead of nichrome. Kanthal is more expensive than nichrome but is certainly not
unaffordable, and it appears that it can tolerate much higher temperatures than nichrome.
Are there any downsides to kanthal wire other than cost?Morgan - 31-1-2016 at 15:53
My limited experience is the connection to the Kanthal has a tendency to over heat but probably my fault for letting it get too hot so the oxide form
which makes a relatively high resistance connection which increases the heating and oxide formation.
Its a good idea to double up the wire at the ends to make the connection but I found that difficult because the wire is so hard. (perhaps annealing
it would help) The connection should be out side of the insulation to keep it cool. I am going to try tig welding next time.
The hand book also gives compatible materials for insulation in contact with the heating elements.JJay - 31-1-2016 at 17:13
That is pretty interesting... I guess I should ask what materials should be used for the terminals of heating elements.wg48 - 31-1-2016 at 19:16
That is pretty interesting... I guess I should ask what materials should be used for the terminals of heating elements.
I don't recall what the handbook or other technical bulletins recommends except that the connection must be sufficiently cool that they does not
corrode which is helped by thicker tails (doubled up tails)
If you consider a copper soldering iron bit at about 200C it rapidly oxidises so a copper connection must be kept well below that temperature.
