Numerical Simulation And Process Optimization Of Die Casting Based On ProCAST

Automobile chassis brackets are an important part of automobile chassis assemblies.Enterprises not only have higher requirements for the surface quality of these components,but also need to meet higher strength requirements.The quality control of automobile chassis bracket castings has not been able to make a perfect breakthrough as a company's production difficulties,and the key to controlling product quality is the design of the mold pouring and drainage system and the setting of die casting parameters.This subject is aimed at the low qualification rate of a certain type of automobile chassis bracket casting produced by a company in Suzhou.It provides data support for improving the qualification rate of products through a combination of professional numerical simulation software,orthogonal test methods and BP neural network prediction.Through numerical simulation analysis of the initial filling and solidification process of the die casting,it is known that due to the uneven thickness of the chassis bracket and the complex structure,the phenomenon of air entrainment and air encapsulation occurs during the filling process.Due to the uneven temperature distribution during the solidification process,the isolated liquid phase region appears,and the subsequent liquid solution cannot be used for shrinkage.When the casting is completely solidified,shrinkage and pores appear in the isolated liquid region.According to the simulation results and defects of the initial scheme of automobile bracket castings,the filling conditions of the isolated liquid phase region were improved by increasing the number of gates,and the structure of the overflow tank was changed to prevent the occurrence of gas trapping.According to the initial simulation results,four process parameters:pouring temperature,initial mold temperature,fast injection speed,and slow injection speed were selected as the research objects that affect the quality of castings.According to the value range of die casting process parameters,an L₁₆?4⁵?orthogonal test is designed,and the porosity of the casting is used as the test target to analyze and compare each group of tests.The optimal process plan is obtained:the pouring temperature is 680?,and the initial mold temperature is 220?,slow injection speed 0.2 m/s,fast injection speed 5.0 m/s.According to the orthogonal table,the influence of the selected process parameters on the quality of the casting is obtained as follows:pouring temperature>mold initial temperature>fast injection speed>slow injection speed.Considering the limitations of orthogonal experiments,the BP neural network was introduced after obtaining the orthogonal experiment results,and the orthogonal experiment results were used as training samples.Predict the optimal process plan of chassis bracket castings:pouring temperature of 680?,initial mold temperature of 220?,slow shot speed of 0.4 m/s,fast shot speed of5.5 m/s.Finally,according to the optimal process plan predicted by the BP neural network toolbox,verification and trial production of chassis bracket castings were performed,and X-Ray flaw detection,metallographic observation and hardness test tests were performed on the samples.It is found that the casting defects are significantly reduced,the quality of the casting meets the requirements for use,and the superiority of the process scheme is verified.The research of this subject shows that:using numerical simulation technology to predict the defects of castings can reduce the number of mold trials and save actual production costs.The combination of orthogonal test and BP neural network optimizes the casting process of automobile chassis brackets,and maximizes the use of the data results of numerical simulation,which effectively improves the efficiency and accuracy of optimization design.Provides fast and effective technical and theoretical support for chassis bracket castings.In addition,the application of neural networks to the production process of die casting can be used as a reference for a wide range of similar die casting production practices,so this topic has certain innovation and application value.