A two-dimensional cellular automaton (CA) model has been developed for thedescription of the normal grain coarsening process. The probabilistic CA method incorporatingMoore's definition of the neighbourhood is use...A two-dimensional cellular automaton (CA) model has been developed for thedescription of the normal grain coarsening process. The probabilistic CA method incorporatingMoore's definition of the neighbourhood is used to simulate the normal grain coarsening process witha new transition rule. The model simulates the grain coarsening process in as much detail that ispossible, from the point of initial nucleation to subsequent coarsening with computational times.The unique result is that the grain coarsening speed can be controlled by the specific method, thisresult is vital to model the grain coarsening quantitatively. In order to make this model valid,experimental work has been done to provide solid evidence for this model. Comparison of themodelling result and the experimental result has been carried out.展开更多
A novel 2D cellular automata (CA) model has been developed for description of normal grain coarsening and abnormal grain coarsening process. The program reflects the grain coarsening quite well even through the averag...A novel 2D cellular automata (CA) model has been developed for description of normal grain coarsening and abnormal grain coarsening process. The program reflects the grain coarsening quite well even through the average grain size becomes very large. Follow results have been obtained: (a) The model reflect the normal grain growth kinetics gradually increase with probability and grain growth speed can be controlled. Based on this result, temperature can be coupled in the model. (b) Abnormal grain growth is modelled successfully. (c) Methodology has been put forward to find the relationship between the experiment results and modelling results. The experimental work on the grain coarsening has been carried out. Graphical output matched the realistic microstructure in every detail. Because many physical parameters can be taken into account in the CA programme, this CA model could not only qualitatively demonstrate the grain growth process, but also quantitatively predict and analyse the grain coarsening process.展开更多
Fukushima accident increases global concern over nuclear safety The accident at the Fukushima Daiichi Nuclear Power Plant in Japan has had an immediate impact on resurgent interest in nuclear power worldwide.Numerous ...Fukushima accident increases global concern over nuclear safety The accident at the Fukushima Daiichi Nuclear Power Plant in Japan has had an immediate impact on resurgent interest in nuclear power worldwide.Numerous governments have announced plans to re-examine nuclear energy policy and review the safety of their reactors and the adequacy of their regulatory frameworks.展开更多
The 2-dimensional cellular automata (CA) simulation technique has been utilized to investigate the abnormal grain coarsening. The growth of abnormal grains is modelled under this assumption that different grains have ...The 2-dimensional cellular automata (CA) simulation technique has been utilized to investigate the abnormal grain coarsening. The growth of abnormal grains is modelled under this assumption that different grains have different boundary energies and boundary mobilities. As temperature increases, some grains may first get rid of the particle pinning effect. Thus a high probability is obtained for atoms to jump over the boundary, so that they can consume other primary retained grains quickly. From the simulation, the characteristics of the abnormal grain coarsening under different conditions are demonstrated successfully. An experiment has also been carried out to reflect the abnormal grain coarsening on the microalloy steel. Simulation results are quite close to the experimental evidence.展开更多
文摘A two-dimensional cellular automaton (CA) model has been developed for thedescription of the normal grain coarsening process. The probabilistic CA method incorporatingMoore's definition of the neighbourhood is used to simulate the normal grain coarsening process witha new transition rule. The model simulates the grain coarsening process in as much detail that ispossible, from the point of initial nucleation to subsequent coarsening with computational times.The unique result is that the grain coarsening speed can be controlled by the specific method, thisresult is vital to model the grain coarsening quantitatively. In order to make this model valid,experimental work has been done to provide solid evidence for this model. Comparison of themodelling result and the experimental result has been carried out.
文摘A novel 2D cellular automata (CA) model has been developed for description of normal grain coarsening and abnormal grain coarsening process. The program reflects the grain coarsening quite well even through the average grain size becomes very large. Follow results have been obtained: (a) The model reflect the normal grain growth kinetics gradually increase with probability and grain growth speed can be controlled. Based on this result, temperature can be coupled in the model. (b) Abnormal grain growth is modelled successfully. (c) Methodology has been put forward to find the relationship between the experiment results and modelling results. The experimental work on the grain coarsening has been carried out. Graphical output matched the realistic microstructure in every detail. Because many physical parameters can be taken into account in the CA programme, this CA model could not only qualitatively demonstrate the grain growth process, but also quantitatively predict and analyse the grain coarsening process.
文摘Fukushima accident increases global concern over nuclear safety The accident at the Fukushima Daiichi Nuclear Power Plant in Japan has had an immediate impact on resurgent interest in nuclear power worldwide.Numerous governments have announced plans to re-examine nuclear energy policy and review the safety of their reactors and the adequacy of their regulatory frameworks.
文摘The 2-dimensional cellular automata (CA) simulation technique has been utilized to investigate the abnormal grain coarsening. The growth of abnormal grains is modelled under this assumption that different grains have different boundary energies and boundary mobilities. As temperature increases, some grains may first get rid of the particle pinning effect. Thus a high probability is obtained for atoms to jump over the boundary, so that they can consume other primary retained grains quickly. From the simulation, the characteristics of the abnormal grain coarsening under different conditions are demonstrated successfully. An experiment has also been carried out to reflect the abnormal grain coarsening on the microalloy steel. Simulation results are quite close to the experimental evidence.
