Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 24 for “"mold filling"”.
-
Numerical Models for Compression Mold Filling
… using the finite element method to study the filling pattern of compression molding. The effects of charge size, temperature-dependent viscosity, mold temperature, and mold closing speed on the velocity and temperature distributions and flow front advancement are investigated.
-
Compression mold filling simulation for thick, nonplanar parts
… model, is developed to study the compression mold filling over three-dimensional curved surfaces. The effects of charge thickness and surface curvature on the pressure and velocity distributions are examined.
-
Modeling Preform Manufacture and Mold Filling for Resin Transfer Molding
… mathematical models for preform manufacture and mold filling should help engineers to design parts and tooling, optimize operating conditions, and shorten the time required to produce low-cost, high-quality net-shape RTM parts.
-
Improvement in Orientation Predictions of High-Aspect Ratio Particles in Injection Mold Filling Simulations
… fiber based polymer composites based injection molded parts provide a light-weight high-strength alternative for use in automobile applications. These composites have enhanced mechanical properties compared to those of pure polymers, if the fibers are oriented in the right direction. One of the …
-
The mechanisms of mold filling and casting defect formation in the lost foam casting process
… to a refinement of current physical models for mold filling and provide additional insight into the formation of casting defects in the process.</p> <p>In Paper 1, castings were poured over a wide range of temperatures using different coating permeabilities. Higher pouring temperature led to …
-
A study of defect formation due to flow instability during mold filling in lost foam casting
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2001.
-
Mold filling characteristics and molecular orientation in injection molding of liquid crystalline copolyesters of poly (ethylene terephthalate)
… boundary layer effect on viscosity and injection molding studies in radial and unidirectional flows were investigated for liquid crystalline (ethylene terephthalate) using Instron model 3211 capillary rheometer. Two copolyesters of PET modified with 60 and 80 mole percent parahydroxy benzoate were …
-
Numerical modeling of incompressible flow applied to casting processes
… of parts with complex shapes. Especially mold filling is of importance, since many features of the cast part are determined in this stage of the process. Concerning the manufacturing of complex industrial parts with high quality even in small numbers, a reliable and predictive numerical …
-
Sensitivity Analysis of Turbulent Free-Surface Flows Applied to Optimal Casting Rigging Design
… are based, was verified against a turbulent filling experiment. The filling times and patterns for a simple mold were studied using water as an analog of liquid aluminum. Further, laminar filling experiments using solutions of glycerol and water were performed. As such, errors in the flow …
-
Effect of vacuum level on the vacuum-assisted resin transfer molding process
Liquid composite molding (LCM) processes have become increasingly popular during the past five decades for the production of complex composite parts. Resin transfer molding (RTM) and structural reaction injection molding (SRIM) are the most widely used LCM processes. These two processes have the …
-
Optimierung des Kokillengießverfahrens auf Schutzgasanwendungen
… of the oxygen concentration in the casting mold atmosphere has a theoretical potential to allow the realization of thin-walled castings and a parallel reduction of defect density, which are both cornerstones of the ongoing developments. In this study it was investigated to what extent the …
-
Verification of a two-dimensional infiltration model for the resin transfer molding process
… time and the pressure increase at the mold inlet associated with the RTM process. Important input data for the model are the compaction and permeability behavior of the preform along with the kinetic and rheological behavior of the resin. The compaction behavior for several textile …
-
Effect of various process variables on the mechanical properties of laminates produced through resin transfer molding process
The increasing interest in the Resin Transfer Molding Process (RTM) evolved from its potential for reducing manufacturing costs, while increasing the capability of manufacturing complex parts. This manufacturing process like many other processes involves a large number of variables, consisting of …
-
Prediction of Fiber Orientation During Processing of Short Fiber Composites
… orientation predictions for the compression mold filling process. The simulation is based on the finite element method and is capable of predicting planar orientation in flat parts of otherwise complicated shape. Comparison with experiments show that the simulation accurately predicts the …
-
Finite element simulation of three-dimensional casting, extrusion and forming processes
… movement of liquid metal-air interface during mold filling process is presented. The developed model predicts the location of the interface (defined by a pseudo-concentration value) by solving for its movement due to forced convection. Also during filling analysis, only the filled and interface …
-
Fiber orientation in injection-molded composites: A comparison of theory and experiment
… orientation are reported for two parts injection molded from nylon 6/6 reinforced with 43 weight percent of glass fibers. The parts are a center-gated disk and a film-gated strip. Orientation is measured from polished cross-sections and reported as a function of position, both across the thickness …
-
Dimensional Stability and Properties of Thermoplastics Reinforced with Particulate and Fiber Fillers
… main causes of warpage observed for injection-molded thermoplastics reinforced with high aspect ratio fibers. Typically, warpage in injection-molded fiber reinforced thermoplastics is primarily attributed to residual thermal stresses associated with shrinkage and thermal contraction of the …
-
Numerical modeling of gravity die casting processes with solidification present during filling
… (Al-5Si) was performed, simulating alloy casting mold filling and solidification with FLOW-3D CAST®’s gravity die casting workspace. Simulations and instrumented castings in the literature have shown casting into a thin plate, monolithic mold cavity using top-gated gravity die casting produces an …
Page 1 of 2