A phase-field study on the formation of the intermetallic Al2Au phase in the Al–Au system
A phase-field study on the formation of the intermetallic Al2Au phase in the Al–Au system
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DOI：
10.1016/j.actamat.2015.05.002
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发表时间：
2015-08
期刊：
影响因子：
9.4
通讯作者：
Fei Wang;B. Nestler
中科院分区：
文献类型：
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作者：
Fei Wang;B. Nestler
通过多相相场模型研究了焊接过程中 Al-Au 体系中金属间化合物 Al2Au 相的生长机制。借助评估的热力学数据（Li et al., 2004），通过假设金属间化合物 Al2Au 相的常规溶液模型，重建了 Al-Au 系统的二元相图。模拟装置是将铝液滴放置在金固体基板的顶部。为了捕获液滴和基底界面相对于周围真空相的相界演化，二元相图被扩展到 Al 和 Au 熔点之间某一特定温度下的三元模型系统。由于Al和Au在液滴/基底界面处的扩散，形成金属间相。在模拟中，我们研究了金属间相的横向和垂直生长速度作为液体金属间化合物表面能的函数。此外，通过考察金扩散率对液-固界面收缩速度的影响，分析了液(Al)-固(Au)界面的不稳定性。
The growth mechanism of the intermetallic Al2Au phase in the Al–Au system during the process of soldering is investigated by a multiphase phase-field model. With the aid of the assessed thermodynamic data (Li et al., 2004), the binary phase diagram of the Al–Au system is reconstructed by assuming a regular solution model for the intermetallic Al2Au phase. The simulation setup is composed by placing an Al-liquid droplet on top of an Au-solid substrate. To capture the phase boundary evolution of the droplet and substrate interface with respect to the surrounding vacuum phase, the binary phase diagram is extended to a ternary model system at one particular temperature between the melting points of Al and Au. Due to diffusion of Al and Au at the droplet/substrate interface, intermetallic phase is formed. In simulations, we investigate the lateral and vertical growth velocities of the intermetallic phase as a function of the surface energy of liquid–intermetallic. Further, the instability of the liquid(Al)–solid(Au) interface is analyzed by examining the shrinking speed of the liquid–solid interface affected by the diffusivity of Au.