Deformation Behavior and Mechanical Properties of Continuous Fiber Reinforced Thermoplastic Composite Laminates in Integrated Overmolding

ABSTRACT Integrated overmolding is an innovative molding technique that combines hot press molding and injection molding for lightweight composite structures. In this study, the deformation behavior and mechanical properties of glass fiber‐reinforced polypropylene composite (GFPP) laminates were investigated through experiments and finite element (FE) simulations. The stress distribution and thickness evolution during molding were analyzed to reveal the mechanisms of laminate deformation. The results showed that stress was concentrated at the rounded corners, leading to thickness reduction and fiber misalignment. The laminate temperature ( T f ) exhibited a dominant influence on the mechanical performance, with tensile and flexural strengths showing region‐dependent trends as T f increased from 170°C to 200°C. Tensile specimens failed mainly by fiber breakage and delamination, while flexural specimens exhibited stepwise wrinkling and interfacial delamination. The study provides quantitative insights into the relationship between process parameters and mechanical properties, offering guidance for optimizing integrated overmolding of continuous fiber‐reinforced thermoplastic composites.