Thermal expansion
Thermal expansion is a physical phenomenon that is observed in many materials, including plastics. Basically, it means that the density of a material changes with changes in its temperature. When the temperature rises, most materials increase in volume, which in turn affects their geometric dimensions. That is, linear dimensions, surface areas and volumes can all change when the temperature changes.
The degree of this change in volume is determined by an important characteristic value, the so-called coefficient of thermal expansion. This coefficient varies depending on the type of material and indicates how much the volume of a material changes per degree of temperature change.
With regard to plastics, it is particularly important to know the coefficient of thermal expansion, since plastics are widely used in many applications and their dimensions must be kept stable under different temperature conditions.
A precise understanding of thermal expansion enables engineers and manufacturers to take these effects into account in the design and application of plastic parts, in order to ensure that they function optimally even under changing temperature conditions.