Thermal conductivity the list of thermal conductivities. These should be considered approximate due to the uncertainties related to material definitions. High energy generation rates within electronics or turbines require the use of materials with high thermal conductivity such as copper "(see: Copper in heat exchangers)", aluminium, and silver. On the other hand, materials with low thermal conductance, such as polystyrene foam and fire brick, are used in building construction or in furnaces in an effort to slow the flow of heat, i.e. for insulation purposes. The reciprocal of thermal conductivity is "thermal resistivity", usually expressed in kelvin-meters per watt (K⋅m⋅W). For a
Electrical resistivity and conductivity is the driving consideration. Electrical resistivity and conductivity Electrical resistivity (also known as specific electrical resistance, or volume resistivity) is a fundamental property of a material that quantifies how strongly that material opposes the flow of electric current. A low resistivity indicates a material that readily allows the flow of electric current. Resistivity is commonly represented by the Greek letter "ρ" (rho). The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). As an example, if a solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is 1 Ω, then the resistivity