Pure Metal Conduction

Most recent answer: 10/22/2007

Q:
Why do pure metals conduct heat better than other metals?
- xiayi (age 13)
Ann Arbor
A:
The heat conduction in metals comes almost entirely from moving electrons. These can carry energy as well as electric charge, so they give both the heat conduction and the electrical conduction.
How easily the electrons flow depends in part on how far they can move without bumping into something and changing directions. You might think that the answer would always be ’not too far’ since the electrons would bump into each atom they encounter. Actually, the electrons travel as waves which can slosh past many atoms without changing directions. However, if there is uneveness in the pattern of atoms the electron waves will bounce off of those irregularities. Metal alloys have uneven patterns of their different types of atoms, so the electrons in them don’t travel around as rapidly as do those in pure metals.

Mike W.

(published on 10/22/2007)