Liquid-Metal Wetting at Grain Boundaries: a Synchrotron-Micro-Radiographic Investigation
Liquid-Metal Wetting at Grain Boundaries: a Synchrotron-Micro-Radiographic Investigation
复制标题
晶界处的液态金属润湿：同步加速器微射线照相研究
DOI：
10.4028/www.scientific.net/ddf.216-217.241
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发表时间：
2003
影响因子：
--
通讯作者：
J. Baruchel
中科院分区：
文献类型：
--
作者：
E. Pereiro;W. Ludwig;D. Bellet;J. Baruchel
液态金属渗入固态金属的晶界会导致固态金属严重脆化。晶界润湿是液态金属脆化的先导过程，其机理至今仍不清楚。本文报道了我们对液态镓进入铝双晶和多晶晶界的传播过程的原位观察。实验采用同步辐射显微照相技术。这种成像技术是很好地适应艾德的原位，非破坏性的散装表征这种现象，由于其合适的空间和时间分辨率。此外，Al和Ga的吸收系数的大的差异是这样的，亚微米厚的液体膜是可观察的，允许实现的动力学分析。因此，实验表明，镓在铝双晶中的渗透前沿大致呈线性时间关系。相反，镓渗透沿着雨边界的多晶体表现出重要的不连续性。
The penetration of liquid metals into the grain boundaries of a solid metal can lead to severe embrittlement of the solid. The mechanism of wetting at the grain boundary, which is the precursor process of liquid metal embrittlement, is still far from being well understood. We report here our in-situ observations of the propagation process of liquid Ga into the grain boundari es of aluminium bicrystals and polycrystals. The experiments were pe rformed using synchrotron radiation micro-radiography. This imaging technique is well adapt ed for the in-situ, non-destructive bulk characterisation of such a phenomenon due to its suitable spatial and temporal resolutions. Moreover, the large difference in absorption coefficients of Al a nd Ga is such that sub-micrometer thick liquid films are observable, allowing the analysis of the kine tics to be achieved. Therefore, the experiments show that the gallium penetration front in aluminium bicr ystal propagates roughly in linear time dependence. On the contrary, the Ga penetration along the rain boundaries of polycrystals exhibits important discontinuities.