摘要 :
In order to predict the shrinkage, warpage and mechanical properties of the injection molded parts, it is necessary to know the history of the flow field during injection-molding processes. In the present investigation a numerical...
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In order to predict the shrinkage, warpage and mechanical properties of the injection molded parts, it is necessary to know the history of the flow field during injection-molding processes. In the present investigation a numerical simulation program was developed to predict the flow field in filling and post-filling stages of injection molding. To simulate the real molding conditions more accurately, a generalized Hele-Shaw model for a non- Newtonian fluid was assumed considering the effects of phase change and compressibility of the resin. A finite-element-finite-difference (FEM- FDM) hybrid scheme with control volume approach was employed as the solving technique.
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摘要 :
Steel components absorb impact energy by plastic deformation whilst composite materials absorbing it by damage mechanisms such as fiber debonding, fiber fracture, and matrix cracking. Therefore, in order to properly substitute met...
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Steel components absorb impact energy by plastic deformation whilst composite materials absorbing it by damage mechanisms such as fiber debonding, fiber fracture, and matrix cracking. Therefore, in order to properly substitute metal components with composite ones in industrial applications, the impact property of composite materials must be well known. In this study, the impact behavior of sheet molding compounds (SMC), which is widely used in automobile industry due to its relatively low cost and high productivity, was examined both experimentally and numerically.
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摘要 :
The accurate prediction of shrinkage and warpage of injection molded parts is important to achieve successful mold design with high precision. In this study, the numerical analysis of shrinkage and warpage of injection molded part...
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The accurate prediction of shrinkage and warpage of injection molded parts is important to achieve successful mold design with high precision. In this study, the numerical analysis of shrinkage and warpage of injection molded parts made of amorphous polymers was carried out in consideration of the residual stresses produced during the packing and cooling stages of injection molding. The temperature and pressure fields were obtained from the coupled analysis of the filling and post-filling stages.
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摘要 :
In bar or rod rolling process, improvement of mechanical properties of the hot rolled products requires numerical prediction of austenite grain size (AGS) for better controlling the microstructural evolution. In this study, a full...
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In bar or rod rolling process, improvement of mechanical properties of the hot rolled products requires numerical prediction of austenite grain size (AGS) for better controlling the microstructural evolution. In this study, a fully three-dimensional finite element (FE) program, which can simulate three-dimensional deformation and heat transfer was integrated with an AGS evolution model available in the literature. It was applied to a four-pass round-oval-round rolling sequence to characterize the AGS distributions depending on the change of roll gap and rolling speed. The predicted AGS distribution obtained from the FE based approach was compared with that obtained from the approximate analytical approach based on elementary theory of plasticity, developed for practical purpose. It was found out that reducing roll gap and increasing the rolling speed leads to fine and uniform grain distribution and recrystallization behavior divided into meta-dynamic and static recrystallization region, respectively. In addition, AGS predicted from the approximate analytical approach was in agreement with that from the FE based approach, but showed discrepancies at higher rolling speed conditions investigated in the present work.
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