Swelling distortion

Swelling distortion is a phenomenon in which materials, especially plastics such as polyamide (PA), swell and deform when exposed to moisture. This occurs when the material absorbs water from the environment, resulting in volumetric expansion. Polyamide is hygroscopic, which means that it easily absorbs moisture, which can affect its dimensions and mechanical properties.

Swelling due to moisture has several effects on the functionality and performance of PA components. For example, it can lead to dimensional changes that affect a precise fit and, in some applications, disrupt the functionality of mechanical joints or moving parts. In addition, swelling distortion can reduce mechanical strength as the material structure is weakened by the additional water. In extreme cases, this can lead to stress cracks or failure of the component.

For applications where exposure to moisture is unavoidable, special formulations of polyamide have been developed that have a lower hygroscopicity. Furthermore, solutions such as coating parts or limiting moisture absorption through design adjustments and storage methods can help control the extent of swelling distortion. It is crucial to understand the impact of moisture on materials such as PA and to take appropriate countermeasures, especially in environments where dimensionally stable and high performance components are required.