Injection Process Optimum And Mold Design Of The Auto Water Chamber Based On CAE

In the context of automobile lightweight,plastics have been increasingly widely applied in automobiles owing to their light weight and excellent performance.The quality of plastic parts is also gaining increasing attention from automobile companies.In recent years,the extensive application of CAD/CAE technology has greatly improved the efficiencies of mold design and process parameter optimization,thereby effectively improving the production efficiency,which has been increasingly valued by companies and researchers.In this paper,automobile water chamber is taken as the study object.Mold design is carried out using CAD/CAE technology,and process parameters are optimized by Taguchi test design,response surface model and genetic algorithm NSGA-II.The main research contents are as follows:Firstly,the application of plastics in automobiles is summarized,as well as the injection molding process.The mechanisms and preventive measures of warpage and shrinkage are analyzed emphatically,and the rationale and application of CAE technology in injection molding are introduced.The 3D design software UG and the simulation software Moldflow are used in combination to simulate the molding process of automobile water chamber based on the mold design criteria to design a reasonable mold structure,thereby shortening the mold development progress.Secondly,a combination of Taguchi test design and CAE technology is used to analyze the effects of mold temperature,packing pressure,packing time,melt temperature and cooling time on two quality assessment indices: warpage and ejection volume shrinkage.Through analysis of means,the influencing regularities of each parameter on the two indices are analyzed.Through analysis of variance,the specific influencing degrees of each factor on the two indices are obtained.Afterwards,the weights for the two indices are calculated using the comprehensive weighted mark method,and a combination of process parameters which gives due consideration to both indices is preliminarily selected.Finally,since the orthogonal test only allows regional optimization,in order to obtain more reasonable process parameters,two factors having the most significant influences on the overall quality are identified as the holding pressure and melt temperature on the basis of Taguchi test optimization.The second-order response surface models of two indices are established separately through the isometric octagonal test design,and their significances are verified.Then,multi-objective optimization is performed on the process parameters using the genetic algorithm NSGA-II to obtain the optimal parameter combination.Moldflow software is used to verify the optimal parameter combination through simulation.The error between the test obtained value and the response surface model predicted value is very small;besides,the optimization result is more prominent than the Taguchi test optimization.The optimized process parameter combination is used in the actual production to produce the products that meet the quality requirements,thus fully verifying the accuracy and efficiency of model prediction.This proves that the integrated application of numerical simulation,response surface model and genetic algorithm provide theoretical guidance and basis for optimizing the process parameters and improving the product quality.