This book explains methods and coding to create FEM-based models to optimize process variables and predict dimensional distortions during the manufacture of thermoplastic matrix composite parts. After investigating defects, such as spring-in, caused by thermal inconsistencies during manufacture, the text offers a step-by-step approach to simulating and predicting the magnitude of distortion via readily available FE codes. Models are validated by testing using the example of a multi-staged roll-formed continuous thermoplastic woven laminate, which can be readily extended to a variety of mold geometries. Information in this book is intended to reduce the need for costly and time-consuming re-tooling in thermoplastic parts design. It includes models and experiments for faster, less expensive manufacture of thermoplastic parts. It is focused on simulating thermal defects in thermoplastics. It covers: techniques for better molds, tooling and equipment; Material Property Testing; Thermoplastic Matrix Composite Manufacturing Methods; and, Process Characterization of Roll Forming.It looks at: Case Study Modeling Approaches and Results; Using Elastic Mechanical Properties; Using Viscoelastic Mechanical Properties; and, Pseudo Meso-Level Decomposition.