Study On The Process Parameters On The Shrinkage And Residual Stress Of Injection Molded Thin Wall Products

With the plastic products are widely used and the rapid development of relatedindustries,the plastic products develop towards thin-wall and precision, people putforward higher requirements on the shape,precision,appearance,etc.In order to reducethe product of warp,save the mould cost and production cycle,it is veryim portant to dothe numerical simulation research of shrinkage and residual stress.The results show thatin injection molding, the residual stress and shrinkage of the product are affected bypressure and temperature.In this paper, we discussed the influences of processingparameters on the shrinkage rate and residual stress by using numerical simulationmethod.This paper analysis the effect of processing parameters on the shrinkage rate andresidual stress,The main work and conclusion of the research are as follows:1.Based on the basic principles of fluid mechanics related and the flowcharacteristics of high temperature plastic melt,the process of injection molding ofproducts was simulated and analyzed by CAE technique,finally it is concluded that thebest screw speed and maximum clamping force, and the change of pressure.in thewhole injection molding process.2.The shrinkage and residual stress of the plastic after the plastic molding has beenresearched.The residual stress curves of each point on the sample are very similar,and issymmetric about the center layer.The surface and central layers is intension stressstate,while in the vicinity of-0.9and0.9is compressive stress state,and from the edgeto the middle of the sample, stress value decreases in turn.The farther away from thegate, the greater the shrinkage, the closer to the center of the plastic,the smaller theshrinkage,and the shrinkage of the plastic is symmetric about the central axis.3. Effect of processing parameters (mold temperature, melt temperature, holdingtime, pressure, pressure curve) on the residual stress and shrinkage has been researchedBy analysis of covariance of single factor.The research results in this paper can provide the theory basis and the advisoryopinion for the injection molding process of High dimensional accuracy and shapeaccuracy of injection molding products.