This paper presents the first-principles investigation on the effect of a silane coupling agent on interfacial adhesive strength with metals. The challenge of this study is to relate atomic-scale phenomena on the interface to stress-strain diagram. Focusing on 3-mercaptopropyl trimethoxy silane (MPS), pure copper and aluminum were selected as the bonding metal. A simple MPS/metal interface model was constructed under a tensile loading condition. First-principles calculations show that MPS exhibits higher interfacial adhesion strength with pure aluminum than with cupper, qualitatively in agreement with the results of the single-lap tensile shear test. It was revealed that the concentrated increase in bond length between specific atoms corresponds to an atomic-scale necking and it forms nonlinear response and a maximum point of stress in a macroscopic stress-strain diagram. It was proved that this first-principles calculation model was effective for the design and development of silane coupling agents suitable for multi-materialization.

本文介绍了硅烷偶联剂对金属界面粘合强度影响的第一性原理研究。这项研究的挑战是将界面上的原子尺度现象与应力应变图联系起来。着眼于3-巯基丙基三甲氧基硅烷（MPS），选择纯铜和铝作为结合金属。在拉伸载荷条件下构建了一个简单的MPS /金属界面模型。第一性原理计算表明，与纯铜相比，MPS与纯铝的界面粘合强度更高，定性与单圈拉伸剪切试验的结果一致。揭示了特定原子之间键长的集中增加对应于原子级缩颈，并且在宏观应力-应变图中它形成了非线性响应和最大应力点。事实证明，这种第一性原理计算模型对于设计和开发适用于多种材料的硅烷偶联剂是有效的。