Thermodynamics and interdiffusion at interfaces with potential jumps, part II

具有势能跳跃的界面处的热力学和相互扩散，第二部分

• 批准号: 166218519
• 负责人: Professor Dr. Markus Rettenmayr (†)
• 金额: --
• 依托单位: Lehrstuhl für Skalenübergreifende Thermodynamische und Kinetische Simulation
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/166218519?language=en
• 关键词: Thermodynamics; interdiffusion; interfaces; potential; jumps

Interfaces in solid or liquid materials are characterized by high chemical and structural disorder. Interfaces are in general far from thermodynamic equilibrium, if two different materials come into contact with each other, or during rapid phase transformations. In the first part of the project, two different models for moving interfaces with a potential jump between the bulk phases were investigated. As a major result the so-called phase-field model with finite interface dissipation has been developed and calibrated using the partner model. It shall now be applied at the mesoscopic scale for the investigation of incomplete partitioning during rapid dendritic solidification. The key question is the inversion of the dependence of the dendrite tip radius on the initial undercooling during the transition towards partitionless solidification. This inversion leads to an increase of the radius with increasing undercooling, instead of the decrease during solute diffusion control. The solidification velocity, however, increases in this regime, according to experimental observations, only slightly, i.e. one would not expect increased trapping according to established theories. The project shall clarify this unexpected behavior.

固体或液体材料中的界面以高度化学和结构无序为特征。界面通常远离热力学平衡，如果两种不同的材料彼此接触，或在快速相变期间。在该项目的第一部分中，研究了体相之间可能发生跳跃的移动界面的两种不同模型。作为一个主要的结果，所谓的相场模型与有限的界面耗散已经开发和校准使用的合作伙伴模型。现在，它应适用于在快速枝晶凝固过程中的不完全分配的调查在介观尺度。关键问题是在向无分区凝固过渡期间，枝晶尖端半径对初始过冷度的依赖性的反演。这种反转导致半径随着过冷度的增加而增加，而不是在溶质扩散控制期间减小。然而，根据实验观察，在该状态下，凝固速度仅略微增加，即根据已建立的理论，人们不会期望增加的捕获。项目应澄清这种意外行为。

项目成果

Solute trapping in non-equilibrium solidification: A comparative model study

非平衡凝固中的溶质捕获：比较模型研究

• DOI: 10.1016/j.mtla.2019.100256
• 发表时间: 2019
• 期刊: Materialia
• 影响因子: 3.4
• 作者: K. Reuther;S. Hubig;I. Steinbach;M. Rettenmayr
• 通讯作者: M. Rettenmayr

Dynamic instability of the steady state of a planar front during non-equilibrium solidification of binary alloys

• DOI: 10.1016/j.jcrysgro.2018.10.008
• 发表时间: 2019-01
• 期刊: Journal of Crystal Growth
• 影响因子: 1.8
• 作者: K. Reuther;P. Galenko;M. Rettenmayr

Effect of convective flow on stable dendritic growth in rapid solidification of a binary alloy

• DOI: 10.1016/j.jcrysgro.2016.07.042
• 发表时间: 2017
• 期刊: Journal of Crystal Growth
• 影响因子: 1.8
• 作者: P. Galenko;D. Danilov;K. Reuther;D. Alexandrov;M. Rettenmayr;D. Herlach

Effect of convective transport on dendritic crystal growth from pure and alloy melts

• DOI: 10.1063/1.4985340
• 发表时间: 2017-07-17
• 期刊: APPLIED PHYSICS LETTERS
• 影响因子: 4
• 作者: Galenko, P. K.;Reuther, K.;Rettenmayr, M.
• 通讯作者: Rettenmayr, M.

Kinetic transition in the order–disorder transformation at a solid/liquid interface

固/液界面有序-无序转变的动力学转变

• DOI: 10.1098/rsta.2017.0207
• 发表时间: 2018
• 期刊: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
• 作者: P. K. Galenko;I.G. Nizovtseva;K. Reuther;M. Rettenmayr
• 通讯作者: M. Rettenmayr