Three Dimensional Dislocation Structure Formed in the Vicinity of Spherical Inclusions

Slip deformation in the vicinity of a spherical shaped inclusion, which is embedded in metal matrix is analysed by a finite element technique. Spatial gradient of the plastic shear strain on slip systems is calculated to evaluate the density components for the geometrically necessary dislocations. Graphical image for the three dimensional structure of the dislocations around the inclusion is reconstructed from the numerical data for edge and screw components of dislocation segments. The obtained results show loop shaped structure around the inclusion, dislocation walls growing nearly perpendicular to the slip plane, and some smaller dislocation loops. Development of these structures is discussed in conjunction with the fluctuation of stress field, which takes place after nonuniform slip process.