【作者】 张丽娜；

【导师】 高英俊；

【作者基本信息】 广西大学 ， 材料学， 2008， 硕士

【摘要】 微合金化是改善铝合金性能的重要手段,一直是铝合金的研究热点。但是合金微结构的演化是一复杂的过程,直接用实验观察比较困难,如果采用计算机随机模拟的方法,即Monte Carlo(蒙特卡罗)方法,便可使问题简单化。近几年国内外学者研究了Monte Carlo算法和晶粒形貌的可视化,并将Monte Carlo方法应用在复杂合金系统、焊接过程和陶瓷烧结过程等领域的晶粒生长模拟,但具体到Al-Cu-Mg合金的微结构的研究,尤其是对微量元素Si、Sc、Zr的微合金化作用的研究还不够深入。本文主要从热力学及动力学理论出发,深入系统地展开了对Al-Cu-Mg合金的微结构演化过程的研究;尝试将动力学理论与蒙特卡罗方法相结合,构建了铝合金的微结构演化模型;并从基合金本身的微结构演化过程研究,推进到含有微量元素的复杂合金的研究领域;进一步深入地揭示了微合金化元素对铝合金微观结构演变的影响与作用机理,得到一系列溶质原子与空位之间相互作用的规律,所得结果与实验相符。本文完成对晶粒生长的完全预测,具有重要意义,且可为材料研究提供新的重要依据。更多还原

【Abstract】 Micro-alloying is an important way to improve the application performance of aluminum alloy,and is a researching hotspot of this field.However,its evolution is a complex process,and this process is difficult to be observed directly by experiment.If the computer simulation(for example the Monte Carlo method)is applied in the research,the calculation process will become easier.Recent years,some scientist has researched the Monte Carlo Method and the visualization of grain morphology,and has applied the Monte Carlo Method to the complex alloy system,welding process and ceramic sintering process.The Monte Carlo method research for aluminum alloy has not been reported in the literature,especially the micro-alloying researches on Si,Sc,Zr are far from enough.Based on kinetics and thermodynamic theory,this paper discussed quite thoroughly the evolution research of the Al-Cu-Mg alloy,and tried to combine the kinetics theory with Monte Carlo method to establish the aluminum alloy evolution model.Based on the base alloy evolution model,the research on complex alloy containing microelement were discussed in simulation.Finally, the essay studied the impact of micro-alloying elements on solute atoms distribution during the initial aging stage to make further understanding of the micro-alloying element’s influence and mechanism,and the laws of the interaction between solute atoms and vacancy were obtained.The simulation results conform to test data.In this paper,the complete the prediction of grain growth simulation is important for the research of the aluminum alloy,can be used as guidance in further research in the field of aluminum alloy microalloying.更多还原