| This thesis focused on the compaction process of powder metallurgy. The compaction process of the iron-based powder was simulated by using finite element based on MSC.Marc. The several major effects on the accuracy of compaction were also discussed.The compaction process of the iron powder forming process and its numerical Micro-Simulation status were introduced. The difficulties in the numerical simulation were also analyzed. Through the comparison of several finite element analysis softwares, an appropriate software for simulation analysis was selected. A complete simulation process was built up. Some problems in simulation such as the boundary conditions,material properties,convergence capacity and so on were solved. The discrete particle simulation of micro-compaction was successfully analyzed by using of MSC.Marc.A test device to measure the friction coefficient was developed. And the interface friction under different pressures was obtained.The effects of the parameters,such as interface friction,pressure,compaction mode,compaction speed and so on,were discussed according to the analysis results of the 2D,3D particle models.The results shows that the higher the compaction speed,the higher the harding of the particles,and the density gradient are.The improvement of the interface friction is beneficial to decrease the work harding of particles and to improve the density distribution,which indicates the interface friction is a key parameter to affect the density value and its distribution.With the increase of the pressure,the green density increase and will gradually tend to be stable when it reaches a certain value.Therefore considering model life and energy sawing,in practical uses,an appropriate pressure must be selected.The established finite element models,the selection of the model parameters, and the relevant conclusions in this thesis are good references for improving the PM forming process and the product quality.
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