The Evolution Of Intragranular Microcracks Within The Metal Materials Due To Two Mass Flow Mechanisms Induced By Electromigration And Stress Migration

In this paper, a finite element method is developed to simulate the evolution of intragranularmicrocraks within the metal materials due to surface diffusion and evaporation-condensation, inducedby electromigration and stress migration.First, a model of intragranular microcrack within the metal materials is presented under the stressfield and surface curvature. Based on the classical theory and the weak statement of surface diffusionand evaporation-condensation, the evolution equations for finite element method under the stress fieldand surface curvature are established. The finite element program is coded to simulate the evolution ofthe two-dimensional microcrack. The reliability and accuracy of the program is also verified.Then, the evolution of intragranular microcraks within the metal materials, under the stress fieldand surface curvature, is simulated. Under the control of the surface diffusion and evaporation-condensation, the program modules, which can analysis the effect of the ratio of the two diffusionmechanisms on the two-dimensional evolution of intragranular cracks, are added to the procedure.The effects of the aspect ratio, the magnitude of the stress, the ratio of the two diffusion mechanismsand other factors on the microcrack evolution are discussed in detail.Finally, the evolution of intragranular microcracks within the metal materials, under the electricfield and surface curvature, is simulated. The effects of the aspect ratio, the electric field, the ratio ofthe two diffusion mechanisms and other factors on the microcracks evolution are investigateddetailedly.