The rate at which heat diffuses through a solid or liquid. Thermal conductivity is measured as the amount of heat conducted per unit time for a given thickness and known temperature difference between the two faces. Testing is usually done on a 1cm x 1cm x 1cm block with a 1 deg C temperature difference. A material with a high thermal conductivity is a good heat conductor. For example, heat conductivities for copper (220), aluminum (122) and steel (25) are given in parenthesis in units of BTU/hour/sq.foot/deg C. A material with a low thermal conductivity is a good heat insulator. For example, heat conductivities for asbestos (0.031), corkboard (0.025) and air (0.014) are given in parenthesis in units of BTU/hour/sq.foot/deg C.
Synonyms and Related Terms
conductivité thermique (Fr.); Wärmeleitfähigkeit (Deut.)