I guess it depends on the context, initially I was making comparisons to heat seeking missiles. In that context, one might use the radar absorbent materials to defeat radar guided missiles, but that trick just doesn’t work with heat, as you can’t “permanently” absorb heat the way you can other kinds of energy. If your vehicle is also generating heat, hiding that is quite difficult.
That is how heat works in general, but that has nothing directly to do with reflecting or absorbing IR.
I guess it depends on the context, initially I was making comparisons to heat seeking missiles. In that context, one might use the radar absorbent materials to defeat radar guided missiles, but that trick just doesn’t work with heat, as you can’t “permanently” absorb heat the way you can other kinds of energy. If your vehicle is also generating heat, hiding that is quite difficult.
You don’t need to absorb it, just emit less. Lower the emissivity and the at the same temperature it will appear colder to a thermal camera etc.