Residual stress of composites during curing process in LCM

Liquid composite molding process(LCM)is a widely used manufacturing technique of composite parts. When thermosetting resins are processed, the shrinkage that results from resin polymerization induce the internal stress in the product, which will affect the product quality. Processing induced residual stress of LCM is studied. The FE-analysis was carried out using the computer program ABAQUS. Cure stage analysis is proceeded to obtain a result file of the temperature and the degree of cure fields, which will be set as the start conditions of thermal-stress analysis. And user define material´s mechanical behavior (UMAT) subroutine is used to define mechanical properties of the materials as a function of the degree of cure. So the residual stress situation of curing stage is achieved.