To predict the segregation effect in metal injection moulding (MIM) injection, a bi-phasic model based on mixture theory is adopted in simulation. An explicit algorithm is developed and realized by the authors, which ...To predict the segregation effect in metal injection moulding (MIM) injection, a bi-phasic model based on mixture theory is adopted in simulation. An explicit algorithm is developed and realized by the authors, which conducts the simulation to be a cost-effective tool in MIM technology. In case of the bi-phasic simulation, the viscosity behaviours are necessary to be determined for the flows of each phase while only the viscosity of mixture is measurable by tests. It is a crucial problem for application of the bi-phasic simulation of MIM injection. A reasonable method is hence analysed and proposed to determine the viscosity behaviours of each phase. Even though this method may be furthermore modified in the future, it results in the practical simulation of segregation effects with reasonable parameters. The simulation results are compared with the measurements on injected specimens.展开更多
In the simulation of the metal injection moulding (MIM), the behaviours of feedstock are much di?erent from which of the polymer injection. It is a mixture of the metallic powder in high concentration and so...In the simulation of the metal injection moulding (MIM), the behaviours of feedstock are much di?erent from which of the polymer injection. It is a mixture of the metallic powder in high concentration and some plastic binder. The advance in simulation of the mould ?lling with such high viscous feedstock is featured by the development of a fully explicit vectorial algorithm. On the basis of previous explicit software realized by the authors, the new algorithm avoids the global solution for pressure ?elds and the use of MINI elements to improve its e?ciency. Except for the operations at element level, neither global solution nor the construction of global matrix is required in simulation. A special strategy is used to regulate the incompressibility condition in ?lled domain at each time step. In case of the MIM problems, this method provides a fast way to simulate the ?lling processes. The computational cost is about linearly proportional to the degree of freedom number. Moreover, this vectorial algorithm can be easily parallelized for high performance computation with multi-clusters. The comparison of numerical results with previous simulations on 3D cases proves the validity and e?ciency of new algorithm.展开更多
文摘To predict the segregation effect in metal injection moulding (MIM) injection, a bi-phasic model based on mixture theory is adopted in simulation. An explicit algorithm is developed and realized by the authors, which conducts the simulation to be a cost-effective tool in MIM technology. In case of the bi-phasic simulation, the viscosity behaviours are necessary to be determined for the flows of each phase while only the viscosity of mixture is measurable by tests. It is a crucial problem for application of the bi-phasic simulation of MIM injection. A reasonable method is hence analysed and proposed to determine the viscosity behaviours of each phase. Even though this method may be furthermore modified in the future, it results in the practical simulation of segregation effects with reasonable parameters. The simulation results are compared with the measurements on injected specimens.
基金Project supported by the Research Fund for the Doctoral Program of Higher Education of China (No. 20020613005)and the French Programme of Alternant Doctoral Training.
文摘In the simulation of the metal injection moulding (MIM), the behaviours of feedstock are much di?erent from which of the polymer injection. It is a mixture of the metallic powder in high concentration and some plastic binder. The advance in simulation of the mould ?lling with such high viscous feedstock is featured by the development of a fully explicit vectorial algorithm. On the basis of previous explicit software realized by the authors, the new algorithm avoids the global solution for pressure ?elds and the use of MINI elements to improve its e?ciency. Except for the operations at element level, neither global solution nor the construction of global matrix is required in simulation. A special strategy is used to regulate the incompressibility condition in ?lled domain at each time step. In case of the MIM problems, this method provides a fast way to simulate the ?lling processes. The computational cost is about linearly proportional to the degree of freedom number. Moreover, this vectorial algorithm can be easily parallelized for high performance computation with multi-clusters. The comparison of numerical results with previous simulations on 3D cases proves the validity and e?ciency of new algorithm.