On the formation of Widmanstätten ferrite in binary Fe–C – phase-field approach
On the formation of Widmanstätten ferrite in binary Fe–C – phase-field approach
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DOI：
10.1016/j.actamat.2004.05.033
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发表时间：
2004-08
期刊：
影响因子：
9.4
通讯作者：
I. Loginova;J. Ågren;G. Amberg
中科院分区：
文献类型：
--
作者：
I. Loginova;J. Ågren;G. Amberg
基于吉布斯能量泛函的相场方法被制定用于 Fe-C 中的 γ→α 转变。导出的相场模型再现了以下重要类型的相变：从通过魏德曼组织的碳扩散控制生长到无碳分配的大规模生长。应用通过 Calphad 技术评估的热力学函数和文献中提供的扩散迁移率，我们研究了从奥氏体晶界发出的铁素体侧板的二维生长。铁素体析出物的形态由高度各向异性的界面能决定。由于大的各向异性值导致不适定的相场方程，我们提出了一种能够规避界面能量的不可微域的正则化方法。
A phase-field method, based on a Gibbs energy functional, is formulated for γ→α transformation in Fe–C. The derived phase-field model reproduces the following important types of phase transitions: from C diffusion controlled growth through Widmanstätten microstructures to massive growth without partitioning of C. Applying thermodynamic functions assessed by the Calphad technique and diffusional mobilities available in the literature, we study two-dimensional growth of ferrite side plates emanating from an austenite grain boundary. The morphology of the ferrite precipitates is defined by a highly anisotropic interfacial energy. As large values of anisotropy lead to an ill-posed phase-field equation we present a regularization method capable of circumvent non-differentiable domains of interfacial energy.