Pultrusion (PDF)

Pultrusion is in principle a simple process to manufacture constant cross sectional fiber reinforced polymer composites. The process has a low labour content and a high raw material conversion efficiency since it is a continuous processing technique. Even if the pultrusion is conceptually quite simple, the analysis of its physics, dynamics and definition of optimal processing parameters, are complex tasks. Keeping the multi-physics and large amount of variables involved in the pultrusion process in mind, a satisfactory experimental analysis for the production requires considerable time which is obviously not a cost-efficient approach. In order to avoid the expensive trial-and-error approaches for designing new products and optimum process conditions, the development of computational process models is needed.This book focuses on the numerical modelling of the pultrusion process. State-of-the-art process models are reviewed and the governing principles are explained in a systematic way. The main challenges in pultrusion such as the process induced residual stresses, shape distortions, thermal history, species conversion, phase changes, impregnation of the reinforcements and pulling force are described and related examples are provided. Moreover, the strategies for having a reliable and optimised process using probabilistic approaches and optimisation algorithms are summarised.Another focus of this book is on the thermo-chemical and mechanical analyses of the pultrusion process for industrial profiles such as rectangular box section, L-shaped profile, I-beam, flat and round profiles in which the process induced stresses and dimensional variations together with the thermal and cure developments are highlighted.