The influence of hydrostatic pressure on the fracture mechanisms of sheet tensile specimens of copper and brass
Abstract The influence of superimposed hydrostatic pressures up to 600 MPa on the tensile fracture mechanism of sheet specimens of α-brass, α-β brass and copper has been studied. Particular attention was paid to the mechanisms leading to the initiation of fracture. At low pressures a common fracture mechanism occurred in all materials which involved the formation of a zone of intense shear deformation followed by fracture due to the development of void-sheets within this zone. At a higher pressure, the magnitude of which increased with the strength of the material, the fracture mechanism changed to one in which fracture occurred at a chisel-edge without any void-sheet formation. In most cases this high pressure fracture mechanism was the result of intense shear deformation in two complementary zones which led to the formation of a ‘V’-shaped trough along one face of the specimen. Fracture occurred when this trough extended through the specimen.