The Heat conductive materials Are those that allow heat to be transferred efficiently between a surface (or a liquid) with high temperature and a lower temperature.
Heat conductive materials are used in different engineering applications. Among the most important applications are the construction of cooling equipment, heat dissipation equipment and in general any equipment that requires heat exchange in its processes.
Conduction of heat in a material
Those materials that are not good heat conductors are known as insulators. Among the most used insulating materials are cork and wood.
It is common for materials that conduct heat well to be good conductors of electricity.
Some examples of good heat and electricity conductive materials are aluminum, copper and silver among others.
Different materials and their respective heat conduction properties can be found in chemistry manuals which summarize the experimental conduction results made on such materials.
Heat conduction
Conduction is the transfer of heat between two layers of the same material or between contacting surfaces of two materials that do not exchange material.
In this case, the heat transfer in the materials is due to the molecular shocks that occur between the layers or surfaces.
Molecular clashes allow the exchange of internal and kinetic energy between the atoms of the material.
Thus, the layer or surface with atoms of greater internal and kinetic energy transfers the energy to the layers or surfaces of lower energy thus increasing the temperature of these.
Different materials have different molecular structures which causes that not all the materials have the same capacity to conduct the heat.
Thermal conductivity
To express the ability of a material or a fluid to conduct heat, the physical property"thermal conductivity"is used which is usually represented by the letter K .
Thermal conductivity is a property that must be found experimentally. Experimental estimates of thermal conductivity for solid materials are relatively simple, but the process is complex for solids and gases.
The thermal conductivity for materials and fluids is reported for a quantity of material with a flow area of 1 square foot, a thickness of 1 foot, for one hour at a temperature difference of 1 ° K.
Heat Conducting Materials
Although in theory all materials can transfer heat, some have better conduction than others.
In nature there are materials such as copper or aluminum that are good conductors of heat, however the science of materials, nanotechnology and engineering have allowed the creation of novel materials with good driving properties.
While a heat conductive material such as copper, found in nature, has a thermal conductivity of 401 W / K m, carbon nanotubes made with thermal conductivities close to 6600 W / K m have been reported.
The values of thermal conductivity for various materials can be seen in the following table:
References
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