It may be good to briefly recollect the heat transfer concept. Heat conduction means that heat is transferred from high temperature to low temperature by molecular agitation within a material without any motion of the material as a whole.
Heat conductivity describes this material property. In metals, heat conductivity is quite high and is primarily due to free electrons. The same mobile electrons which participate in electrical conduction also take part in the transfer of heat.
Heat conductivity in non-metals is much smaller than in metals and is mainly due to lattice vibrations. Such heat transfer is often described in terms of "phonons", quanta of lattice vibrations. (Do not confuse with "photons", which are quanta of electromagnetic radiation.)
The rate of heat transfer is proportional to the heat conductivity and also to the temperature difference between the spots with different temperatures.
Heat conductivity describes this material property. In metals, heat conductivity is quite high and is primarily due to free electrons. The same mobile electrons which participate in electrical conduction also take part in the transfer of heat.
Heat conductivity in non-metals is much smaller than in metals and is mainly due to lattice vibrations. Such heat transfer is often described in terms of "phonons", quanta of lattice vibrations. (Do not confuse with "photons", which are quanta of electromagnetic radiation.)
The rate of heat transfer is proportional to the heat conductivity and also to the temperature difference between the spots with different temperatures.
Jan
P.S.: An example:
Assume that the edge was heated up during sharpening from the room temperature 70°F to 470°F (yellow colour).
The mass of the heated edge was 0.1% of the total mass of the whole blade. How large will be the equilibrium temperature when we neglect blade cooling by the air?
Answer: Equilibrium temperature caused by the heat transfer within the blade will be 70.4°F. Really an imperceptible difference.
Assume that the edge was heated up during sharpening from the room temperature 70°F to 470°F (yellow colour).
The mass of the heated edge was 0.1% of the total mass of the whole blade. How large will be the equilibrium temperature when we neglect blade cooling by the air?
Answer: Equilibrium temperature caused by the heat transfer within the blade will be 70.4°F. Really an imperceptible difference.