基于相场模拟的倾斜共晶生长研究进展  

Research Progress on Tilted Eutectic Growth Based on Phase Field Simulation

作　　者：罗磊 李向明[1] 魏岑 王献 LUO Lei;LI Xiangming;WEI Cen;WANG Xian(School of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China)

机构地区：[1]昆明理工大学材料科学与工程学院,昆明650093

出　　处：《材料导报》2020年第11期11114-11120,共7页Materials Reports

基　　金：国家自然科学基金(51961018,51561016)。

摘　　要：共晶合金是工业上应用最为广泛的一类合金,其组织形态以两相或多相固态从液态中同时共生生长为主。共晶组织存在于许多重要的结构材料和功能材料的固液相变中,而倾斜共晶是共晶组织在诸多因素影响下形成的与热流方向呈一定倾斜角度的共晶组织。学者们探究了倾斜共晶生长的生长机理和共晶生长界面稳定性等重要问题,发现倾斜共晶组织有利于改善共晶组织的材料性能,对解决许多关于共晶组织的问题有指导意义。初步认为,具有各向异性的表面张力对倾斜共晶产生影响。由于相场法的固液界面序参数连续变化,解决了凝固过程中固液界面追踪困难的问题,因此可利用相场模拟法来研究倾斜共晶的形成机理。采用相场模拟法研究倾斜共晶的生长机理,主要是通过改变物理参数和相场参数来观察倾斜共晶组织形貌的变化规律,例如各向异性参数、温度梯度、凝固速度、对流情况、界面能比以及初始层片间距等诸多参数都对倾斜共晶的形貌演化具有一定的影响。通过相场模拟法对凝固过程中倾斜共晶生长进行研究可以得到每种材料对应的最佳物理参数和相场参数,这不仅在理论上更是在工业上上升了一个新的台阶。历经几十年的发展,相场法模型从单相到多相,从定性研究到定量研究,更是从二维相场模拟发展到三维相场模拟,相场模拟法越来越完善,对于凝固过程中组织形貌变化模拟结果也越来越接近实际情况。本文将从二维相场模拟与三维相场模拟出发,阐述了在不同维度下物理参数和相场参数分别对倾斜共晶组织形貌演化的影响。在二维相场模拟方面,学者们取得了一系列的突破,证明了各向异性和对流情况对倾斜共晶有一定的影响,初始层片间距会改变共晶的生长模式,温度梯度、界面能、凝固速度和扩散系数对共晶倾斜角度也有一定影Eutectic alloys are the most widely used type of alloys in industry.Their microstructure is characterized by the simultaneous growth of two-phase or multi-phase solids from liquids.Its eutectic structure exists in the solid-liquid phase transition of many important structural and functional materials.And tilted eutectic is eutectic microstructure formed under the influence of many factors at a certain angle to the heat flow direction.Researchers began to explore the mechanism of tilted eutectic growth and the interface stability of eutectic growth.Tilted eutectic structure is beneficial to improve the material properties of eutectic structure,and has a guiding significance for solving many problems related to eutectic structure.It is believed that the surface tension with anisotropy has an effect on the production of tilted eutectic.Due to the order parameters continuous change of the solid-liquid interface in the phase field method,the problem of difficult tracking of solid-liquid interface during solidification is eliminated.The phase field simulation method is used to study the mechanism of tilted eutectic formation.The phase field simulation method was used to study the tilted eutectic growth mechanism,mainly by changing the process parameters and phase field parameters to observe the variation of the tilted eutecticmiscrostructure.For example,anisotropic have certain influence on the morphological evolution of tlited eutectic,and other parameters such as temperature gradient,solidification rate,convection condition,interfacial energy ratio and initial lamellar spacing have an important influence on the morphological evolution of tilted eutectic.By simulating the growth of tilted eutectic in solidification process with phase field method,the optimal physical parameters and phase field parameters corresponding to each material can be obtained,which is a new step not only in theory but also in industry.After decades of development,the phase field method has evolved from single-phase to multi-phase,from qualitat

关 键 词：倾斜共晶 相场模拟 各向异性 共晶 形貌演化 

分 类 号：TG141[一般工业技术—材料科学与工程]