A Study On The Structural Features And Molding Defects Of The Rear Case Of The Display

With the continuous development and progress of the plastic industry,plastic products account for an increasing proportion in people’s lives,and people’s requirements for the performance and appearance of plastic parts are also increasing.Among them,the display back shell is more and more widely used due to its advantages of light weight,good heat resistance and good surface gloss.Injection molding is the most important processing method for the back shell of the display,and defects such as warpage of the injection molded parts during the injection molding process have a great influence on the quality and performance of the injection molded parts.At home and abroad,the research on the warpage caused by the structural characteristics of the injection-molded shell is very limited.Most of them only study the defects of injection-molded parts in terms of process and so on.For this reason,they have certain limitations.Based on this,this paper selects the display case of similar parts containing multiple common features to study the relationship between its structural characteristics and warpage.Based on the theory of group technology,through the analysis of the structure and performance of the back shell of the injection-molded display,the typical shell injection parts-the back shell of the display were selected as the research object.By analyzing its structural characteristics,the dimensions,buttons,base,heat dissipation device and connection holes are extracted as the research objects,and the back shell models with different structural characteristics are established.Based on Moldflow,the same pouring system and cooling system are established for each model.By comparing the plastic raw materials,it is determined that the back shell injection material is ABS,and the best process parameter combination was obtained by orthogonal test and other methods.The flow analysis and cooling analysis of each feature model were performed.The warpage analysis module in the Moldflow simulation software was used to analyze the warpage of the rear shell model with different characteristic parameters,and the relationship between the structural characteristics of the rear shell of the display and its warpage deformation was studied.Origin9.1 was used to establish the relationship between different structural characteristic parameters and maximum warpage.According to the curve type,suitable fitting tools are selected to fit the data to obtain the mathematical expressions of the structural parameters and the maximum warpage deformation,and the calculation results obtained by using the mathematical relationship are compared with the simulation results.The results show that the simulation results It is very close to the calculation result,and then shows the rationality of the mathematical model.This paper provides a basic mathematical model for the structural design of the display back shell,and provides some new ideas for the research of the injection back shell.