I have a thin nichrome wire that will be heated up to approx 100 degrees C, inside an enclosure. Since this wire needs to follow a specific path I would like to attach it somehow at some points along that path. Now my question is what material I could use to wrap the wire at those points as to limit the amount of heat dissipated through direct contact at those points.

When looking on the internet I found plenty of insulation materials that can resist high temperatures, but their main purpose is to insulate the electricity going through the wire, not the heat radiated from it. I would need a material that blocks as much heat as possible so the outside would be as cool as possible. This to avoid having all the heat from the wire transferred through the attachments into the plastic of the enclosure, which could melt the plastic at the attachment point. Maybe ceramic can be used for this?

What I was thinking about doing was put some insulation around the wire above the attachment point and clamp the insulated wire to the attachment point. If I were to clamp the wire directly, using bolts and nuts for instance, the heat transfer from the wire through those bolts and nuts would heat up the plastic way too much and it would start getting soft.

Since I am 3d printing my enclosure I can use plastic that can withstand 80 degrees (printing with PETG), which is clearly not enough for this case. Even using nylons I can only go up to 110, which is too close to the wire temperature.

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    \$\begingroup\$ Not an answer, but something to keep in mind: The wire will expand/contract with temperature. Not only do you need to design this into your path, but it can cause repeated rubbing (and breakage) at the connection points. \$\endgroup\$ – bitsmack Feb 15 '18 at 20:22
  • \$\begingroup\$ @AndrewMorton I just checked for mica, and I read on Wikipedia: "Specifically, mica is unusual in that it is a good electrical insulator at the same time as being a good thermal conductor". This sounds like the opposite of what I am looking for. This seems to conduct heat rather than block it. \$\endgroup\$ – Joris Mans Feb 16 '18 at 0:18

In general, braided fiberglass sleeve type insulation would work. You can check out some possibilities at Cables Ties & More. You could perhaps use several layers for more insulation.

  • \$\begingroup\$ Thanks. Ordered some of that stuff on eBay. Going to test it asap. \$\endgroup\$ – Joris Mans Feb 16 '18 at 0:33

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