Achieving Class A appearance on fiber-reinforced substrates: Challenges and solutions

摘要

Achieving a Class A appearance over fiber-reinforced substrates can be a challenge. We discuss the evolving measurements used to characterize top-coated surface appearance. The influence of carbon fiber on the surface appearance of a thermoplastic RTM substrate is related to differences in thermal expansion within the substrate. The mechanism identified here is then extended to several chopped-fiber-filled thermoplastic substrates where the fiber-mapping effect has a different manifestation. We then investigate the influence of thickfilm applications on the appearance of the Class A surface. Our analysis finds that changes in both the depth as well as the width or wavelength of the substrate affect the ability of thick films to cover fiber mapping.