The term **“thermal conductivity”** describes a material’s capacity to transmit or transfer heat. In addition to the letter “k,” it can also be represented by the symbols “” and “.” **Thermal resistivity is the name given to this quantity’s reciprocal**. High thermal conductivity materials are employed as heat sinks, whilst low thermal conductivity materials are used as thermal insulators.

The rate at which heat is transported through a material is proportional to the negative of the temperature gradient and is also related to the area through which the heat flows, according to Fourier’s law of thermal conduction (also known as the law of heat conduction). The following equation can be used to express this law’s differential form:

q = -k.∇T

Where q stands for the thermal flux or heat flow, T stands for the temperature gradient, and k stands for the material’s thermal conductivity.

#### Formula

Each material has a unique ability to transmit heat. The following formula describes a material’s thermal conductivity:

K = (QL)/(AΔT)

Where,

- Thermal conductivity, measured in W/m, is K.K
- Q is the heat transmission rate (in Joules/second or Watts) through the material.
- Between the two isothermal planes, L is the distance.
- A represents the surface’s area in square meters.
- T is the Kelvin difference in temperature
- Thermal Insulation system