Study On Optimization Of Injection Molding Process For Automobile A-pillar Fabricated With Green Composite Materials

Due to the sustained growth of vehicle ownership,the attendant energy consumption and environmental pollution problems are becoming severe.For this reason all countries over the world are trying to explore the new directions of car development,and automobile lightweight is one of the most feasible directions.Currently,using composite materials instead of steel materials is an effective way to achieve the lightweight of the car.Enlarging the application range of natural fiber in the automobile industry draws the attention of many experts and scholars owing to the renewable and environmentally friendly characteristics of natural fiber.This thesis aims to optimize the injection molding process of auto interior parts manufactured by green composite materials.The A-pillar of automobile was taken as the research object,while the flax fiber reinforced polypropylene composite material was used for injection molding material.The numerical simulation and orthogonal experiment method were used to optimize the A-pillar injection molding process.The main work of this article is as follows:(1)Firstly,the three-dimensional model of A-pillar was established by CATIA v5 software,and then the A-pillar model was repaired by using the CAD doctor module of Moldflow software.Secondly,the A-pillar model was meshed and repaired by applying Moldflow Insight.Finally,a reasonable A-pillar injection molding system was created based on the specific dimensions of the A-pillar and the relevant design principles.(2)Four groups of tests were set up according to the different aspect ratio of flax fiber in this thesis.In these tests,the warp deformation of A-pillar was regarded as an evaluation index,and the fiber content,packing pressure,filling time,mold temperature,melt temperature,packing time were considered as investigation factors.According to the relevant data and production experience,the level of the various factors were determined,and then selecting the appropriate orthogonal table to optimize the process parameters of A-pillar injection molding.(3)During the optimization tests,the warp deformation was chosen as the evaluation standard of A-pillar forming quality.In light of the A-pillar injection molding simulation results,the influence of the process parameters on the warpage of A-pillar was studied by the range analysis method,finding out the influence degree of each process parameter on the warpage of A-pillar.The further study of the simulation results showed that the effects of fiber content and packing pressure on the warp deformation of A-pillar were the most significant.Therefore,the regularity and trend of warp deformation with fiber content and packing pressure were analyzed.The optimized process parameters of each group were verified,and ultimately the optimal process parameters of each group were ascertained.