Warpage analysis of a micro-molded parts prepared with liquid crystalline polymer based composites

The purpose of this study is to understand the warpage behavior of a micro-injection molded part induced by anisotropy of the material. Microstructural anisotropy was characterized to understand warpage behavior of liquid crystalline polymer based composites. A new definition of the microstructure was introduced along the thickness of a molded part, i.e., “skin–shear–core” layer was proposed depending on the orientation of LCP molecules and fillers. The microstructural anisotropy of LCP composites was verified by using WAXD, CT, and SEM analyses. The anisotropic elastic modulus and coefficient of thermal expansion (CTE) of micro-injection molded parts were investigated by using a new numerical method with the modified Mori–Tanaka (M–T) model. The interaction coefficient, CI, and coefficient of thermal expansion (CTE) were the most important factors determining the warpage of a micro-injection molded part made of an anisotropic material. The control of warpage due to the orientation of glass fibers was investigated by simulation.