How Can You Limit Heat Transfer Between Two Metallic Objects?

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Tuatha
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Looking for some help here. If I have two objects, (1) a heat source that, let's say can get up to 1500 degrees, and (2) a simple metallic object, and let's say the object and heat source are relatively close to each other. Object number (2) has a small metallic probe that goes into the heat source and connects to itself. Is there a way to regulate the temperature of object (2) through this metallic bridge, wherein, although the heat source may produce a temperature of 1500 F, object (2) does not get above 500 degrees? I thought of using a bimetallic coupler (on the metallic probe), but not sure if that would work. Any materials that regulate, limit heat exchange? Thanks.
 
How much energy is flowing from source to sink (the metallic object)? All you need to remember is that you can control the temperature between two objects, or you can control the rate of heat flow between two objects, but you can't control both at the same time. So, a material with lower conductivity will yield the high temperature difference you want, but it will reduce the flow of heat going from the source to object 2, and the heat could end up going elsewhere, perhaps in another direction you don't intend.

When you say a small gap, that makes me think you'll need a very low conductivity material, or, in other words, an insulator. At the temperatures you're seeing, it will likely need to be a high temperature insulation. I bought some a while back from McMaster Carr, but you can get it other places too. In any case, make sure the thing that is being insulated won't get warmer if it's covered up by a piece of insulation, cause that could change the system as well. If the heat has other places to go though without affecting what it is you're studying or building, then there shouldn't be any problems.
 
Tuatha said:
Looking for some help here. If I have two objects, (1) a heat source that, let's say can get up to 1500 degrees, and (2) a simple metallic object, and let's say the object and heat source are relatively close to each other. Object number (2) has a small metallic probe that goes into the heat source and connects to itself. Is there a way to regulate the temperature of object (2) through this metallic bridge, wherein, although the heat source may produce a temperature of 1500 F, object (2) does not get above 500 degrees? I thought of using a bimetallic coupler (on the metallic probe), but not sure if that would work. Any materials that regulate, limit heat exchange? Thanks.
Thermal conductance varies with temperature in most materials. Especially those with solid-liquid phases. But they are not very adjustable and such selecting the right material for your application will be complex.

What has been used is a thermal pipe, which conducts heat by gas and or gas/liquid. They can be adjusted by controlling the internal pressure.
But I'm not sure if you are looking for a negative or positive temperature response from your thermal coupler. Basically if the temperature rises from 1500 to 1550, what should your coupler do, transmit more or less?
 
Isn't what the OP is describing just a high temperature insulator?

Make the insulation sufficiently thick & the object shouldn't get hotter than your limit. Am I wrong?