Segregation of impurity to the grain boundary and interphase boundary in ultra-fine microstructure

超细显微组织中杂质向晶界和相间偏析

• 批准号: 07455271
• 负责人: ISHIDA Kiyohito
• 金额: $ 4.8万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07455271/
• 关键词: Grain boundary segregation; Grain size; Interface; Thermodynamics; Gain boundary; Impurity; Segregation energy

Theoretical and experimental study of the effect of grain size on the grain boundary segregation was made and the results obtained are as follows ;1.The equilibrium segregation of solute to the grain boundary can be described by the modified Mclean's equation :2.The grain size effect on the intergranular segregation is remarkable with higher segregation energies and lower bulk concentrations with decreasing temperature.3.When the segregation free energy of X is larger than that of Y in A-X-Y ternary alloy, the grain boundary concentration of X atom decreases with decreasing grain size, while that of Y atom depends on the bulk concentrations of solute.4.An experimental evidence of the grain size dependence of the intergranular segregation in Cu-0.0015at.%Bi alloy was obtained.5.The segregation energy of Bi in Cu was estimated to be about 62.5kJ/mol.6.It is suggested that the grain size has a significant role on the grain boundary segregation not only in the metallic system but also in ceramics.

本文从理论和实验两方面研究了晶粒尺寸对晶界偏聚的影响，结果表明：（1）溶质向晶界的平衡偏聚可用修正的姆克林方程描述：2.晶粒尺寸对晶间偏析的影响显著，随着温度的降低，偏析能增大，体相浓度降低。3.在A-X-Y三元合金中，当X元素的偏析自由能大于Y元素时，X原子的晶界浓度随晶粒尺寸的减小而减小，而Y原子的晶界浓度则取决于溶质的体浓度5.计算了Bi在Cu中的偏聚能为62.5kJ/mol。6.表明晶粒尺寸对金属系和陶瓷系的晶界偏聚有重要影响。

项目成果

K.Ishida: "How the grain size affects the grain boundary segregation?" Current state on High Strength Steels, The Iron and Steel Institute. 87-92 (1995)

K.Ishida：“晶粒尺寸如何影响晶界偏析？”

K.Ishida: "Effect of Grain Size on Grain Boundary Segregation" J.Alloy & Compounds. (印刷中). (1996)

K.Ishida：“晶粒尺寸对晶界偏析的影响”J.Alloy &compounds（出版中）。

K.Ishida: "Effect of grain size on grain boundary segregation" Journal of Alloys and Compounds. 235. 244-249 (1996)

K.Ishida：“晶粒尺寸对晶界偏析的影响”合金与化合物杂志。