Improvement And Application Of Microstructure Model

Two aspects of the simulation of microstructure model have been studied in this dissertation: 1. The RCP-LV microstructure model has been improved to be a better representation for the geometrical structure of real materials; 2. We do the computer simulation about the aspect of application of stereology based on the RCP-LV microstructure model.A new algorithm to simulate the random close packing of unequal spheres and disks is designed and developed ,which is categorized into collective rearrangement model, and Laguerre_Voronoi diagram is used to speed up the procedure.This can speed up the procedure and expand the model scale. Although the RCP-LV microstructure model is superior to other models for its varieties, it still can not be considered as a perfect polycrystal model because the shapes of the Voronoi cells are too regular comparing with real materials. So we employ the improved and optimization method to the RCP-LV microstructure model. The final simulation result shows that the improved RCP-LV model not only inherits the advantages of the original RCP-LV model, moreover, its geometrical characterization becomes more consistent with the real material.On the other hand,we do abundant computer simulation about the application of stereology. Because the size of the grain size has a important effect on properties of polycrystalline materials, it is one of the most important characteristic parameters of the polycrystalline material structure. So on the research and manufacture process of the polycrystalline materials, it is attached importance to the control and the assess of the size of the grain size or the structure.We do abundant computer simulation to compute average chord length and average section area. And then on the basis of stereology essential formula and the standard of ASTM E112, we compute average grain size ,and we use 2D parameters of stereology to compute 3D Grain size distribution.At the end of the dissertation, some proposals are put forward for the future research.