Department of Mechanics and Engineering Science, Shijiazhuang Railway Institute, Shijiazhuang 050043, China;
Department of Mechanics and Engineering Science, Shijiazhuang Railway Institute, Shijiazhuang 050043, China;
Department of Mechanics and Engineering Science, Shijiazhuang Railway Institute, Shijiazhuang 050043, China;
two-phase medium; piezoelectricity; screw dislocation; stress intensity factors; image force;