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With the development of the aerospace , biomedical and other high-tech , precision injection molding technology and more extensive applications , which also proposed to increasing demands for precision injection molding technology . The residual stress is a common molding defects in the injection molding technology , it not only affects the appearance of the quality of the products , but also seriously affect the optical, electrical , mechanical properties of the products . In the injection molding process , the residual stress of the article , including the residual stress of the thermal residual stress and flow . Due to thermal residual stress an order of magnitude larger than the flow of residual stress , academia and simulation software usually ignore the residual stress of the flow of products or simply attach a correction factor . For optical grade products , however , the flow residual stress severely affects the performance of the light transmittance of the article , especially some of the sophisticated optical lens lenses . This article from the photoelastic principle , combined with the dynamic transmission type visualization technology, developed a set of optical grade products, dynamic stress visualization experiment system , and the system of the formation mechanism of the flow in a rectangular cavity residual stress distribution law system research . By comparing products under different process parameters and mold structure birefringence stripes difference , combined with the polarizing microscope the the calculation and moldex3D software product flow residual stress the different cavity structure in the different mold temperature , the polymer melt flow filling the shear shear stress , temperature field, pressure field simulation , summed up the injection temperature , packing pressure , mold structure and temperature on the flow of residual stress law . Optical grade products injection molding process for guiding criteria . By precision injection molding visualization experiment system , visually study the flow behavior of the three typical rectangular cavity high-temperature melt in the cavity , and the research was supported by a rectangular cavity products weld lines and injection mechanism of defect formation . By analyzing the intrinsic link between the mold structure design , molding process parameters and macro melt flow behavior and products macroscopic defects , proposed specific measures to resolve the weld line and injection flaws .
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