论文标题
多组分合金中的相边界分离：漫射界面热力学模型
Phase Boundary Segregation in Multicomponent Alloys: A Diffuse-Interface Thermodynamic Model
论文作者
论文摘要
显微合金元素倾向于将基质 - 原始相边界分离以减少界面能量。隔离机制正在成为一种新型的设计策略，用于开发降水硬合金，并在高温应用中显着提高了耐耐药性。在本文中，我们报告了一种纳米散射界面热力学模型，该模型描述了两相替代合金中的多组分隔离行为。遵循晶界的经典方法，我们采用常规溶液热力学来建立隔离等温线。我们表明，该模型恢复了描述局部界面浓度的Guttmann多组分等温线，以及控制总溶质过量和界面能量的广义Gibbs吸附等温线。对于模型的两相季四元合金，证明了各种多组分隔离行为。界面参数的性质和所得的分析解决方案使该模型可与原子计算和实验特征进行参数化和比较。
Microalloying elements tend to segregate to the matrix-precipitate phase boundaries to reduce the interfacial energy. The segregation mechanism is emerging as a novel design strategy for developing precipitation-hardened alloys with significantly improved coarsening resistance for high temperature applications. In this paper, we report a nanoscopic diffuse-interface thermodynamic model that describes multicomponent segregation behavior in two-phase substitutional alloys. Following classical approaches for grain boundaries, we employ the regular solution thermodynamics to establish segregation isotherms. We show that the model recovers the Guttmann multicomponent isotherm describing local interfacial concentrations, and the generalized Gibbs adsorption isotherm that governs the total solute excess and interfacial energy. A variety of multicomponent segregation behaviors are demonstrated for a model two-phase quaternary alloy. The nature of interfacial parameters and the resulting analytic solutions make the model amenable for parameterization and comparison with atomistic calculations and experimental characterizations.
