What is the most probable cause of distortion in nonmetallic assemblies?

The most probable cause of distortion in nonmetallic assemblies is high temperature exposure. When nonmetallic materials, such as plastics or composites, are subjected to high temperatures, it can lead to softening or warping. Many nonmetallic materials have a temperature threshold beyond which their structural integrity is compromised. At elevated temperatures, these materials may experience altered properties, including a loss of rigidity and dimensional stability, leading to distortion.

Water intrusion can cause other problems such as degradation or weakening of the material, but it is not the primary cause of distortion. Mechanical stress typically leads to failure modes like cracking or breaking rather than mere distortion, and improper installation may lead to misalignment or operational issues but not directly to material distortion. Thus, exposure to high temperatures remains the key factor in causing distortion in nonmetallic assemblies, highlighting the importance of thermal management in the design and operation of these components.