Heterogeneous nucleation of ßSn on NiSn4, PdSn4 and PtSn4
Heterogeneous nucleation of ßSn on NiSn4, PdSn4 and PtSn4
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NiSn4、PdSn4 和 PtSn4 上 Sn 的异相成核
DOI：
10.1016/j.actamat.2014.02.044
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发表时间：
2014
期刊：
影响因子：
9.4
通讯作者：
Belyakov S
中科院分区：
文献类型：
--
作者：
Belyakov S
在无铅焊接过程中，βSn通常需要高的成核过冷度，并且正在努力开发成核催化剂。结果表明，NiSn 4、PdSn 4和PtSn 4是βSn的异质形核剂，当这些金属间化合物存在于钎料中或作为界面层时，可使β Sn的形核过冷度降低到104 K。在具有（OR）（1 0 0）Sn取向关系的XSn 4晶体的（0 0 8）晶面上，βSn成核催化作用发生||（0 0 8）XSn 4和[0 0 1]Sn|| [1 0 0] XSn 4，其中存在105%的平面晶格匹配。该OR也是良好排列的片状β Sn-XSn 4共晶形态的起源，即使共晶包含小于2 vol. %的多面NiSn 4、PdSn 4或PtSn 4。
During Pb-free soldering, βSn often requires a high nucleation undercooling and there is an ongoing effort to develop nucleation catalysts. It is shown here that NiSn4, PdSn4and PtSn4are heterogeneous nucleants for βSn, reducing the nucleation undercooling to ∼4 K when these intermetallics are present either in the bulk solder or as the interfacial layer. Nucleation catalysis occurs by βSn nucleating on the (0 0 8) facet of XSn4crystals with an orientation relationship (OR) (1 0 0)Sn||(0 0 8)XSn4and [0 0 1]Sn||[1 0 0]XSn4where there is a planar lattice match of ∼5%. This OR is also the origin of well-aligned lamellar βSn–XSn4eutectic morphologies, even though the eutectics contain less than 2 vol.% of faceted NiSn4, PdSn4or PtSn4.