Structural transformations and deformation localization effects during nonuniform explosive loading of metallic balls

Continuous balls 60 mm in diameter made from steels, brass, and duralumin are subjected to the explosion of a spherical charge initiated from the surface at several points. The microstructural studies of the loaded balls demonstrate that the macro-and microstructural changes in them and their fracture correlate with the geometric conditions of the shock-wave action. Cracks form at the sites of shock-wave intersection according to the loading geometry and the initial fibrous structure of the material. Localized-flow regions are observed near cracks, and the appearance of these regions precedes crack nucleation. In the brass ball, radial cracks coalesce with its central cavity forming in a solid state. The possibility of cumulation for the same loading schemes is shown to depend on the material.