INTERACTION OF A SCREW DISLOCATION WITH AN INTERFACIAL EDGE CRACK IN A TWO-PHASE PIEZOELECTRIC MATERIAL

The interaction of a screw dislocation with an interracial edge crack in a two-phasepiezoelectric medium is investigated.Closed-form solutions of the elastic and electrical fields induced bythe screw dislocation are derived using the conformal mapping method in conjunction with the imageprinciple.Based on the electroelastic fields derived,the stress and electric displacement intensityfactors,the image force acting on the dislocation are given explicitly.We find that the stress andelectric displacement intensity factors depend on the effective electroelastic material constants.In thecase where one of two phases is purely elastic,the stress intensity factor and image force are plottedto illustrate the influences of electromechanical coupling effect,the position of the dislocation and thematerial properties on the interaction mechanism.