Structure of boundaries in composite materials obtained using explosive loading

Abstract

We have presented the results of studying the fine structure of interphase boundaries for a number of composite materials obtained by methods of explosive welding and explosive compacting of powder mixtures. Joints of different metals (titanium-low-carbon steel, copper-tantalum) and metals with refractory carbides (chromium carbide-titanium) have been investigated. Under welding, pairs differed from each other by the type of interaction. It has been found that, in these composites, interphase boundaries exhibit a final thickness on the order of 200 nm, throughout which the composition of the material changes gradually from a composition that corresponds to one of the components of the composite to a composition that corresponds to the second component. It has been shown that the structure of interphase boundaries is complex. With the limited solubility of components along boundaries, two fairly thick crystalline interlayers are detected, the total thickness of which is equal to the total thickness of the boundary; between the interlayers, there is a thin (to 5–7 nm in thickness) interlayer with a crystalline or amorphous structure.