Monte Carlo Simulation Of Microstructure Evolution In Ceramics Sintering Process

Ceramics with special properties can meet the need of modern science and technology development and has been widely used in aerospace, construction, machinery, electronics and other fields. Ceramics properties are closely related to its microstructure, so studying microstructure evolution process in ceramics sintering process is essential. The traditional methods of studying ceramics microstructure evolution were focused on theoretical analysis and experiments. Along with the development of computing technology, computer simulation has become another important research tool. Although computer simulation methods are various, yet non-iterative Monte Carlo calculation method which has relatively little calculation and short simulation time, is widely used in simulating ceramics microstructure evolution.An improved Monte Carlo method to classical Monte Carlo method was established from grain growth probability, grain orientation choice methods, growth rate control of grain and porosity, and a microstructure evolution simulation program in ceramics sintering process was developed. The program simulates ceramics microstructure evolution under different physical parameters, process parameters and scale parameters, and furthermore gives grain morphology, grain size and porosity during evolution. The program was used to simulate ceramics microstructure evolution under different sintering temperatures and times. Meanwhile, through nanoα-Al2O3 ceramics sintering experiments under different sintering temperatures and times, the comparison was done between the experimental results and simulation results. The main conclusions are as follows:1. The new Monte Carlo method is able to simulate the microstructure evolution in ceramics sintering process much better, and simulation accuracy and speed has been greatly improved.2. Simulation results show that as simulation temperature and simulation time increase, the grain size of ceramics keeps growing and the porosity continuously reduces, which is consistent with the theoretical analysis.3. In the sintering simulation of single-phase ceramics and two-phase ceramics, the grain growth index is 2.03 and 3.12, respectively at 1573K, as obtained by fitting calculation of the grain sizes. This is basically consistent with the theoretical values of the grain growth index (2 for single-phase material and 3 for two-phase material). The simulation results of simulation program in this paper and the theoretical situation have a better consistency.4. By Comparison with Al2O3 sintering experiment, it was found that the grain size and porosity in the simulation results well coincide with the experimental data, consequently, improved Monte Carlo method can well simulate the evolution of the structure in ceramics sintering process.