Glass-fiber reinforced polyurethane foam composite manufactured by long fiber injection process lfi: lightweight potential investigations through mechanical properties and micro- structure characterization
Résumé
The Long Fiber Injection (LFI) is an innovative economic competitive manufacture process which combines injection and fiber spray-up technology to produce Glass Fiber Reinforced PU Foam composite (GFRPUF). Projected into open molds, LFI process allows complex shape, integrations of functionals components, a large weight reduction. We explored the lightweight potential of GFRPUF composites by using a highly foamed PU matrix about 175 kg.m3 and incorporating fiber mass content up to 50%. Mechanical properties tests were performed in compression and 3 points bending, while the real sprayed up fiber content and the fiber orientations were checked with a burn-off procedure and image processing. Influence of fibers incorporated contents on foam microstructure were also evaluated with Scanning Electron Microscopy and micro-computed tomography. Correlation on mechanical properties/microstructure was clearly demonstrated and wide alteration of the foam structure was observed starting from 30-35% mass content for the prepared GFRPUF composites