Microstructure of Austenitic stainless Steel Explosively Bonded to low Carbon-Steel

Abstract

An austenitic stainless steel plate was explosively bonded to low carbonsteel plate, and tbe microstructure of the bonded composite has been investigated by transmission electron microscopy. The bond zone of several μm width consists of a mixture of stainless steel and low carbonsteel, and each component metal is composed of small crystal grains of several thousand Å size. The dislocation density in the small grains is of the order of 109/cm2. The regions, of about 10 μm width, immediately adjacent to the bond zone consist of either small crystal grains or elongated grains of several thousand Å width. The dislocation density in these regions is 109–1010/cm2. Outside these regions crystal grains in the stainless steel as well as the low carbon-steel are much larger, and contain the high dislocation density of 1010–1010 /cm2Tangled dislocations, dislocation loops, and undeveloped cell structure are observed. In addition to the dislocations, in the stainless steel profuse deformation twins of 50–230 A width are seen except the regions near the bond zone, while no significant hep e-phase is detected. The formation of the small gralns in the bond zone and in its neighbouring regions are considered.