A Review of Fiber-Reinforced Injection Molding: Flow Kinematics and Particle Orientation

ABSTRACT: The existing flow and particle orientation models applicable to fiber-reinforced injection molding are reviewed. After a brief description of injection molding, previous studies on the flow kinematics and fiber reinforcement are presented. Basics of Hele-Shaw flows are described Including the commonly used viscosity models and foun-tain flow effects. Some of the existing models for particle orientation are analyzed with particular emphasis on the amsotropic description of the material system. Concentration regions for short fiber suspensions are defined and relevant constitutive equations are dis-cussed. A few example solutions are also given which describe the three-dimensional ori-entation field for the filling of a sudden expansion cavity, depicting skin-core orientation structure. 1