Insights on Processing and Properties of Polymer Matrix Composites

The manufacturing of reliable and high quality composite parts requires the optimization of processing parameters. This article addresses the issue of understanding how polymer composite matrix properties develop during the manufacturing process and how they can be modelled and predicted. The optimized selection of pertinent processing parameters (time, temperature, and pressure) can dramatically increase cost-effective manufacture of composite parts. It can also be a powerful tool to reduce phenomena such as warpage, residual stresses, microcracking and fiber/matrix failures, which strongly affect the performances and the integrity of the final product. However, process modelling of composite polymer-based matrices is difficult, mainly because of the dramatic properties change and the complex interaction occurring among the properties during the manufacturing process. Mechanical tests for advanced composite materials conform in many respects to the conventional test typology used for traditional isotropic materials. Despite the complication associated with the heterogeneity of composite systems, the interface between fiber and matrix, and the anisotropy at micro- and macroscopic levels, the same characteristic property definitions generally used for conventional materials can be identified for these novel materials. In some cases additional constants are required and some differences in nomenclature are introduced specially when no isotropic counterpart exists. The evolution of test methods to meet new demands has continued over the years. This article reviews those mechanical test methods that have achieved a well-established general consensus.