Can substances conduct heat without heating up?

[DuckAmuck]

Just wondering if there are substances (even just theoretical ones) able to conduct heat without heating up itself. How does that operate? What properties are different from that of ordinary substances?

 

[Vanadium 50]

You mean that if you had a reservoir at T1 (say 350K), another one at T2 (say 400K), and a conduit at T3 (say 300K), you could transfer heat from the second reservoir to the first without changing T3? The answer is no.

 

[vin300]

Say heat conducts from body at 100 degrees through material A to interface at 50 degrees, further flowing through material B to extremity at 0 degrees. If you observe that during transfer, the interface at 50 degrees is heating up, it means that it wants to reduce transfer through material A and increase through material B, so that rates through A and B are equal. Similarly, if 50 degrees begins to cool down, it means material A is a poorer conductor than material B, hence it has to adjust itself so that differential through material B is reduced and differential through material A rises, to compensate for poorer conductivity, so that transfer rates are balanced. It works this way only in series conduction.