Papers by Author: Han Yun Li

Abstract: By using the real information of the intended bonding surface and considering the effect of the diffusion distance in a definite time, a new theoretical model for diffusion bonding was proposed. The model, reflecting the characteristic of real bonding process effectively, realizes the visualization and simulation of the bonding process in which many voids disappear dynamically. The results show that the simulation is close to those experimental results from the phenomena of voids closure.

Abstract: The problem involving a center crack in a rectangular piezoelectric body under anti-plane mechanical shear loading and plane electrical loading is analyzed for the permeable crack face conditions. The so-called general solutions of stress and electric fields are obtained, which is satisfied both the governing equations of anti-plane problems and the boundary conditions of the crack face. It is shown that electric field is nonsingular near right crack tip, while strain, stress and electric displacement have crack-tip singular behavior, the energy release rate has the same form as that without the electromechanical interaction, which is always positive. At last, the boundary collocation method is used to calculate the energy release rate. Numerical values are obtained to show the influence of the material properties and the electric field. The results show that the method of half analytical and half numeral is simple, accurate and widely applicable.