Abstract
Weight reduction is important to improve fuel efficiency of vehicles, as it reduces carbon dioxide(CO2) emission. Recently, thermoplastic materials have been applied to whose structural parts. We have developed a thermoplastic backdoor module for compact minivan,`NISSAN LAFESTA´, whose backdoor is made of all olefin plastic. Inner panel is made of glass fiber reinforced polypropylene, which has high strength and rigidity. Long fiber thermoplastics(LFT) Injection molding techniques which can keep fiber length long have been applied to inner panel. Deformation of inner panel during lifetime are calculated by CAE analysis and material creep property. Outer panel material also has high impact resistant polypropylene, and is designed with welding, flowability, impact behavior. All olefin plastic backdoor could achieve approximately 15% of weight reduction, compared to steel one. We have succeeded in shortening development period by utilizing CAE (mechanical analysis and mold flow analysis).
Keywords: Olefin plastic, door, injection molding, weight reduction, integration