Being a wide variety of thin-layered interconnection components in electronics packaging with relatively small scale and heterogeneous materials, conventional numerical methods may be time consuming and even inefficac...Being a wide variety of thin-layered interconnection components in electronics packaging with relatively small scale and heterogeneous materials, conventional numerical methods may be time consuming and even inefficacious to obtain an accurate prediction for the interface behavior under mechanical and/or thermal loading. Rather than resort to a fully spatial discretization in the vicinity of this interface zone, an interface model was proposed within the framework of micropolar theory by introducing discontinuous approximation. A fracture description was used to represent the microscopic failure progress inside the interface. The micropolar interface model was then numerically implemented with the finite element method. As an application, the interface behavior of a packaging system with anisotropic conductive adhesive (ACA) joint was analyzed, demonstrating its applicability and great efficiency.展开更多
A detailed fracture mechanics analysis of bridge-toughening in a fiber reinforced composite is presented in this paper. The integral equation governing bridge-toughening as well as crack opening displacement (COD) for...A detailed fracture mechanics analysis of bridge-toughening in a fiber reinforced composite is presented in this paper. The integral equation governing bridge-toughening as well as crack opening displacement (COD) for the composite with interfacial layer is derived from the Castigliano's theorem and interface shear-lag model. A numerical result of the COD equation is obtained using the iteration solution of the second Fredholm integral equation. In order to investigate the effect of various parameters on the toughening, an approximate analytical solution of the equation is present and its error analysis is performed, which demonstrates the approximate solution to be appropriate. A parametric study of the influence of the crack length, interfacial shear modules, thickness of the interphase, fiber radius, fiber volume fraction and properties of materials on composite toughening is therefore carried out. The results are useful for experimental demonstration and toughening design including the fabrication process of the composite.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.10702037)the Shanghai Pujiang Program(Grant No.08PJ14054)the Innovation Program of Shanghai Municipal Education Commission (Grant No.09YZ01)
文摘Being a wide variety of thin-layered interconnection components in electronics packaging with relatively small scale and heterogeneous materials, conventional numerical methods may be time consuming and even inefficacious to obtain an accurate prediction for the interface behavior under mechanical and/or thermal loading. Rather than resort to a fully spatial discretization in the vicinity of this interface zone, an interface model was proposed within the framework of micropolar theory by introducing discontinuous approximation. A fracture description was used to represent the microscopic failure progress inside the interface. The micropolar interface model was then numerically implemented with the finite element method. As an application, the interface behavior of a packaging system with anisotropic conductive adhesive (ACA) joint was analyzed, demonstrating its applicability and great efficiency.
基金National Natural Science Foundatjon and China Postdoctoral Scjence Fbundation
文摘A detailed fracture mechanics analysis of bridge-toughening in a fiber reinforced composite is presented in this paper. The integral equation governing bridge-toughening as well as crack opening displacement (COD) for the composite with interfacial layer is derived from the Castigliano's theorem and interface shear-lag model. A numerical result of the COD equation is obtained using the iteration solution of the second Fredholm integral equation. In order to investigate the effect of various parameters on the toughening, an approximate analytical solution of the equation is present and its error analysis is performed, which demonstrates the approximate solution to be appropriate. A parametric study of the influence of the crack length, interfacial shear modules, thickness of the interphase, fiber radius, fiber volume fraction and properties of materials on composite toughening is therefore carried out. The results are useful for experimental demonstration and toughening design including the fabrication process of the composite.
