Advanced Structures & Composites Center

Published: 2018

Publication Name: Electronic Theses and Dissertations

Publication URL: https://digitalcommons.library.umaine.edu/etd/2935/

Abstract:

Thermoplastic-matrix composite materials have unique advantages over traditional thermosets including faster processing, improved fracture toughness, and recyclability. These and other benefits have caused increasing interest in the use of these materials in both aerospace and automotive industries. Due to the differences in behavior, these materials require a different type of manufacturing process to thermoset matrix composites. This manufacturing process generally involves using pre manufactured tape-layers. These layers, containing both thermoplastic-matrix and fiber-reinforcement, are aligned to the desired orientation, and stacked up into a “tailored blank” using an automated tape layup machine. They are then heated to the thermoplastic melting temperature in an oven and stamped to shape using a large press. Due to some complex behaviors in processing, however, it is necessary to simulate the forming process prior to manufacturing. Simulation can help to avoid costly trial-anderror type process tuning in order to avoid manufacturing defects like wrinkles and tears and to optimize the use of material. A research effort has been undertaken in order to streamline the process of material characterization toward simulation, which are accomplished using commercially available software. This includes a variety of material characterization tests, as well as forming tests in order to compare simulated results, such as predicted wrinkles and fiber reorientations in complex-shaped parts, to real parts manufactured under the same conditions as the simulations. Finally, a tool has been developed which allows the extension of these forming simulations to inform more accurate structural analyses of as-formed parts.