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Optimal Composition of Light-weight BMC (Bulk molding compound) for automotive headlamp reflector using Glass bubble was investigated. Glass bubble (G/B) normally has low heat conductivity which has a bad influence on cycle time making products like reflectors. It was very important to improve the productivity of Light-weight BMC by means of finding optimal composition of base resin, curing agent and other additives. This study focused on the ideal ratio of each component of BMC, unsaturated polyester resin, glass bubble, inorganic filler, glass fiber and additives. Mechanical and environmental properties of the product which was made of optimized light-weight BMC were evaluated to compare with the properties of the product which was made of existing BMC.

Since the environmental problems and new stricter regulations are forcing the industries to introduce more ecological materials for their products, biodegradable materials have attracted increasing attention. Among these materials, Polylactic acid (PLA) is remarkable for its modulus, strength, chemical resistance. However, PLA could not be used for automobile industries for its low heat resistance and impact strength. Therefore, in this study natural fiber was introduced as reinforcements in order to improve the properties of PLA. And for various experiments, Polypropylene (PP) was used as matrix resin instead of PLA. Especially for improving the properties of PLA composites, surface treatments, annealing, and adding rubber elements were performed. With surface treatments, we found that the mechanical properties of composite were improved. And with annealing treatment, we found the remarkable increase of heat resistance of PLA composite.

Corrosion stiction at the contact interface between a brake friction material and a gray iron disc under the parking brake condition was investigated by evaluating the possible parameters that affect the shear force to detach the corroded interface. Using production brake friction materials, comprising non-steel and low-steel types, corrosion tests were carried out by pressing the brake pad onto the gray iron disc using a clamp at various conditions. Results showed that the shear force to detach the corroded interface tended to increase with applied pressure and corrosion time. On the other hand, porosity, acidity, and hydrophobicity of the friction material did not show a reliable correlation to the stiction force. The poor correlation of the stiction force with the friction material properties indicated that the stiction force was not determined by a single factor but governed by multiple parameters including surface contact areas and inhomogeneity of the ingredients.