Interface Fracture Analysis Based On The Interfacial Dislocation Theory

With the social development of science and technology, manufacturing in engineering materials to the quality requirements of the structure more and more is also high,interfaces are widely existing in all kinds of research objects. It is contrary to the fact that applications of fracture mechanics will present some problems which are stress oscillating and tumbling in crack surface material as material destruction in the research for the difference of materials. In order to overcome this shortcoming, to get the reasonable description and explanation for the interface fracture, in this paper, the stress field of interface dislocation is obtained by integral transformation, the singularity of stress oscillating is avoid by comparing with conclusions we have of fracture mechanics, replacing Dirac function with normal distribution function when the basic solution of fracture mechanics is applied in interface analysis. The character of Cauchy kernel solution are retained, combining physical significance of the oscillating term, so stable fracture parameters is got by replacing Dirac function with normal distribution function. Then the fracture mechanics boundary value problems are changed into the first singular integral formula based on the basic solution of interface dislocation. Avoiding the singularity of stress oscillating, and getting the stable domain of point force, the results show that the variation of fracture parameter is agreement with the experiment data by the domain to solute the interface fracture problems. The main contributions are as follows:The stress field of interface dislocations is obtained by using integral exchange method .According to the consistent of interface dislocation and physical picture of crack, in the basic solution the point force using Dirac function is given to the physical interpretation and mathematical explanation, which makes the fundamental solution of fracture mechanics analysis be used for the interface level of the dislocation solution, avoid the stress oscillatory singularity.Dislocation pileup with a simulation of the interface crack initiation behavior, is obtained by numerical simulation the relations of stable normal parametersεand the crack length,which is seven thousandths of the Crack length nearby.The problems of interface fracture are soluted by using normal distribution parameterε. Fracture mixing degree is obtained. Numerical results show that the model can be used to solve the interfacial fracture problem. And it doesn't only avoid using the second class of singular integral equations, but also avoid the complexity which is brought by interface model which has been obtained by using excessive physical assumptions.