▎ 摘　　要

A type of novel Sn-Bi/Graphene nanocomposite was proposed as thermal interface material. The mechanical properties of Sn-Bi/Graphene nanocomposite were investigated by theoretical calculation as a function of the weight fraction of graphene. The stress distribution of single lap shear test of the Sn-Bi/Graphene nanocomposite solder was simulated by finite element method. The enhancement mechanism of Sn-Bi/Graphene composite was studied further by a 3-dimensional Sn-Bi/Graphene nanocomposite micro model. The strength of lap joint was mainly influenced by shear stress and initial crack occurs at the edge of lap joint. The shear modulus and strength of Sn-Bi/Graphene nanocomposite lap joint increased with the weight fraction of graphene. The shear modulus of Sn-Bi/Graphene nanocomposite was similar to 192% greater than pure Sn-Bi alloy when the content of graphene increased to 1.0 wt.%. The graphene reinforcement improved stress strength as graphene leading an effective stress transfer. Stress concentration was existed near the edge of graphene, where the initial failure may occur. The novel Sn-Bi/Graphene nanocomposites are promising application as a thermal interface material with improved mechanical properties in the near future. (C) 2014 Elsevier B.V. All rights reserved.