Research On The Structure Design And Plasitc Injection Molding Process For The Rear Bumper Of The Commercial Automobile

Plastic pars are widely applied in aero-space, electronic industries, mechanism, shipping and automobile due to their advantages such as light weight, good flexility, chemical-resistant, electricity insulation, excellent forming property, etc. With the development of economy, automobiles are much more popular and familial, and more requirement to interior and exterior tirms are proposed. The structure design and forming property of the plastic parts gain plenty attention because that plastic parts are the main components of the automobile interiror and exterior trims. With the exhausting of global resource and the automobile lightweight conception being widely absorbed, the percentage of plastic parts in automobile parts is gradualy increasing. At the early period of the development for big size exterior injection parts such as automobile rear bumper, it is hoped that both rationality structure and less forming difficulty are considered. Therefore, it is important to study on the structure design and plastic injection molding process of rear bumper of the commercial automobile.Based on the structure design principle and plastic injeciton molding process of the rear bumper of commericial automobile, the3D geometric models of the rear bumper is established by the CAD software UG, which provide useful foundation for the futher study on its static pressure analysis and plastic injection molding simulation.The finite element linear model of different structure design of the rear bumper is developed in the FEM software ANSYS, which is convenced its validity by comparing the results of bench test and simulation. Based on this model, the effects of different materials and thickness on stiffness of the rear bumper have been discussed througn static analysis. The effect of different mounting holes arrangements on modal has been investigated. Meanwhile, reasonable explain and improvement plan are proposed for local subsidence occurred in practice use. The results provide useful reference for the structure design of the rear bumper of the commercial automobile in practice.Based on the Visual Basic language and Moldflow, the software named "Evaluation System of Plastic Injection Moldfing CAE Simulation" is developed. Fuctions, such as a variety of plastic material selection and material properties inquiry optimal selection of a variety of plastic material, process parameters setting and analysis, many groups of process parameters optimization, analysis results view are achieved.