Material advice: low thermal conductivity, high melting point and machinable

[chopper75]

I'm looking for a recommendation for a material to be used for soldering fixture. Material needs to have low thermal conductivity, ba able to withstand the heat and be machinable.

 

[MikeHalloran]

Corning MACOR machinable ceramic.
I think McMaster carries it and similar stuff from Cotronics.


Mike Halloran
Pembroke Pines, FL, USA

 

[tomwalz]

We sue fire brick and tile in similar applications.

tom

Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

 

[btrueblood]

Macor is a resonable choice k = 1.5 W/m-K. The green, machinable stuff will pickup solder flux and wet to solder over time, better results if you bake it out after machining.

Fused (sintered) amorphous boron nitride can be k = 3 W/m-K. Machines well with abrasive tools, though it's a bit brittle and weak, but it has lovely non-stick properties for braze/solder tooling. You can buy it in rods and plates from McMaster-Carr, amongst other sources.

Foamed silica (Space Shuttle heat shield tile material) is one of the lowest conductivity materials around (

http://www.cotronics.com),

k = .19 W/m-K. This stuff too is brittle and weak, but can be machined easily with abrasive bits (heck, with a pocketknife too). Also very low wettability to molten metals, fluxes, etc.

 

[Compositepro]

You could also cover a metal part with fiberglass fabric.