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Carbon fiber sheet molding compound (SMC) is an attractive material for automotive lightweighting applications, but several issues present themselves when adapting a process developed for glass fiber composites to instead use carbon fibers. SMC is a discontinuous fiber material, so individual carbon fiber tows must be chopped into uniform rovings before being compounded with the resin matrix. Rotary chopping is one such method for producing rovings, but high wear rates are seen when cutting carbon fibers. Experiments were performed to investigate the wear progression of cutting blades during rotary carbon fiber chopping. A small rotary chopper with a polyurethane (PU) backing and thin, hardened steel blades was used to perform extended wear tests (120,000 chops, or until failure to reliably chop tows) to simulate the lifespan of blades during composite material production.

Surface quality plays an important role on aesthetic appeal of any exterior component of a vehicle. As such, smooth and defect-free are some of the critical characteristics of an automotive surface. Numerous manufacturing-related factors such as production environment, substrate material, coating material, handling is known to generate defects to inherently decrease the overall quality of the external surface. Many of these defects tend to be localized while spreading over large areas of the surface. However, the vast majority of available systems are unable to unequivocally quantify surface defects, and, in most cases, the surface quality assessment is performed in a relative and rather qualitative manner. To address this, the main goal of the present study was to develop a new laser light-based technique capable to detect and quantify the localized defects that are present on the surface of reflective components for automotive exteriors.

Retroreflective (RR) optical elements play a critical role in signaling, safety, and aesthetic/styling functionality of automotive lighting. The commonly-used inverted corner cube (ICC) RR structures with hexagonal aperture have several critical limitations that are primarily rooted in their manufacturing technique that involves complex assemblies/shapes of hexagonal pins and electroforms, particularly in case of freeform surfaces. This study introduces a novel RR micro-optical structure, namely: right triangular prism (RTP). The geometric model underlying this new geometry is defined as the intersection between a cube and a plane placed in a particular relative orientation with respect to each other. Following this, non-sequential optical simulation studies were performed analyzing the effect of incident light orientation. Advanced optical functionality of the RTP with a width of 450 μm was obtained as practically unattainable through conventional hexagonal pin-bundling technology.