Solid-state phase transformations involving solute partitioning: modeling and measuring on the level of individual grains
Solid-state phase transformations involving solute partitioning: modeling and measuring on the level of individual grains
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DOI：
10.1016/j.actamat.2004.06.030
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发表时间：
2004-09
期刊：
影响因子：
9.4
通讯作者：
S. E. Offerman;N. Dijk;J. Sietsma;E. Lauridsen;L. Margulies;S. Grigull;H. Poulsen;S. Zwaag
中科院分区：
文献类型：
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作者：
S. E. Offerman;N. Dijk;J. Sietsma;E. Lauridsen;L. Margulies;S. Grigull;H. Poulsen;S. Zwaag
提出了一种简化的多晶材料固相转变过程中生长相邻颗粒扩散场由非重叠向重叠转变的简化模型。该模型是基于用三维X射线衍射显微镜对中碳钢中奥氏体分解为铁素体和珠光体的独特观察建立的。该模型解释了观察到的三种先共析铁素体晶粒长大和奥氏体晶分解，以及间接观察到的分解奥氏体晶间的碳交换。模型与实验在单晶水平上的直接比较表明，铁素体颗粒的长大与局部碳浓度和局部形核密度密切相关。报道了相变前奥氏体晶尺寸不稳定和铁素体振荡生长的异常观察结果。
A simplified grain growth model is presented for the transition from non-overlapping to overlapping diffusion fields of growing neighboring grains during partitioning solid-state transformations in polycrystalline materials. The model is based on unique observations on the austenite decomposition into ferrite and pearlite in medium-carbon steel with the three-dimensional X-ray diffraction microscope. The model explains three types of observed pro-eutectoid ferrite grain growth and austenite grain decomposition, and the indirectly observed carbon exchange between decomposing austenite grains. A direct comparison of the model and the experiment at the level of individual grains shows that the growth of ferrite grains is strongly related to the local carbon concentration and the local density of nuclei. Unusual observations of a non-stationary austenite grain size prior to the transformation, and oscillatory ferrite growth are reported.