In-situ monitoring method and influencing factors of in-mould melt rheological behavior in fine/micro injection molding
Existing monitoring methods based on the plasticizing unit of injection molding machines are difficult to apply accurately to analyze the melt state within the mould.Additionally,in-mould rheological monitoring techniques are limited by narrow gap fine structures,leading to insufficient applicability and potential damage to the surface aesthetics of the product.To address these issues,a method for in-situ monitoring of melt viscosity using the in-mould fine channel structure characteristics in injection molding was proposed.Online measurement of the rheology of polymer melt processing was realized with arrangement measurement modules within the mold flow channel and the integration of replaceable insert structures.The change rules of the size effects of the in-mould measurement channels under different process parameters and channel structures were specifically investigat-ed,as well as the impact of plasticizing temperature,injection pressure,and mould temperature on the flow state of molten polymers.The results indicate that the size effect of the measurement channel increases with the reduction of the diameter of the channel.The size effect rises with the increase of injection velocity and decrease of plasticizing temperature.The polymer melt's viscosity in mould is mainly affected by the plasticizing temperature,while the influences of injection pressure and mould temperature on the viscosity of the melt are limited.The proposed in-situ monitoring method for in-mould melt viscosity successfully characterizes the melt state inside complex fine moulds in injection molding,and the layout design of measurement modules in the mold flow channel does not affect the surface quality of the products.This method expands the monitoring techniques of in-mould processing rheology and provides reference for quality control development in injection-molded precision fine/micro structure products.
万方数据
维普
