This term describes the formation of fine cracks in plastics caused by the combined action of mechanical stress and certain environmental media. The cracks often occur without significant external load when the material is already subjected to internal stresses, for example due to processing or assembly. Chemical influences such as solvents, cleaning agents, or oils can further accelerate this process. In plastics engineering, this phenomenon is a common cause of failure because it can lead to brittle fracture of the component. Prevention includes proper material selection, low-stress processing, and suitable operating conditions.

Stress cracks in Injection Molding


Quality: Stress cracks in a polystyrene moulded part


Related topics:

Stress corrosion cracking
Internal stress
Environmental stress cracking

This glossary of plastic industry is provided by PLEXPERT Canada Inc.