Basic Research On Design And Manufacturing Technology Of Automotive Interior And Exterior

With the development of automotive industry,the majority of interior and exterior trim of commercial vehicle are made of plastic material by using injection molding. In the process of automotive interior and exterior product development, material selection, the product structure design, injection molding production process conditions and other factors not only directly related to the functional performance of automotive interior and exterior, but also will affect the vehicle quality and the cost of vehicle development. Therefore, study on the influence of plastic material properties, product structure design and molding process parameters on automotive interior and exterior product performance have become hot topics with high scientific and practical significances. The aims of this dissertation are to research the influence of plastic material properties and molding process parameters on automotive interior and exterior product performance, and to establish a automotive interior and exterior product design supplementary system. The research results can provide a theoretical basis and practical guidance for the development of automotive interior and exterior. The main contents of this dissertation are listed as follows..(1) Based on testing of materials, the influences of ingredients and content of PP on properties of composite materials were analysed.(2) FE model and bench test bench were established by using an analytical method as well as a nano-indentation test. The influences of material properties on mechanical properties and forming property of products were analysed by finite element simulation experiment of structural strength/stiffness analysis and forming analysis. Also, material formula system were established and validated.(3) FE model of an automotive interior product was established and the simulation analysis were carried out in the Moldflow software. The influences of process parameters (time, tempreture, pressure) under different injeciton process on injection molding process and forming quality were analysed.(4) A simplified analysis model was designed under the mechanism of sink-mark defects generating. By using DOE method, influences of factors and interreaction of each other on sink-mark of the model were researched, and mathematical model of the relationship between factors and response (factors and sink-mark) was established. Sink-mark defect of the model was minimizing in injection molding through response surface regression modeling and intelligent algorithm, the results have been validated. Also, this method was applied to process design of actual product.(5) The related knowledge of material selection, structure design and other key aspects in the development process were summarized, code designed, and program transformed to become computer readable data. Physical model, overall and module design, computer realization and security management of the system were established by using knowledge base and structured query language. Material technology database and computer-aided system of automotive interior and exterior were established to help the designer to select materials and desing product structure.