A novel coupling simulation scheme for elastoplastic problems of multiscale structures in electronic packaging

Abstract

With the increasing of packaging density and functional diversity, electronic packaging structures with multiscale features have brought huge demand. To analyze elastoplastic problems of multiscale structures in electronic packaging, this paper presents an efficient coupling scheme of Abaqus and a self-written boundary element method (BEM) code. In the numerical analysis, based on the geometric features of the multiscale structures, the whole domain is divided into two domains: FE domain and BE domain. The Abaqus is used in the FE domain where non-linear or nonhomogeneous behavior is expected, whereas the linear elastic domain or large-scale domain is solved by the BEM code. The BE part in the whole FE-BE model is defined as a super element (user-defined element in Abaqus) of the FE, and its effective stiffness and effective nodal forces at the interfacial boundary are evaluated by the BEM code and assembled by the user subroutine (UEL) into the FE system. Users not only benefit from the powerful functions of Abaqus, but also can use BEM as a complement to improve solution accuracy. The numerical example shows that the stress results obtained by the scheme are in a great agreement with the results obtained by a detailed finite element model.