Microstructure and mechanical properties of copper-tantalum joints produced by explosive welding

Microstructure and mechanical properties of copper and tantalum joints produced by explosive welding technology were characterized. It was established by structural analysis technique that mixing of copper and tantalum at the interface occurs due to a nonequilibrium process. The mixing zone consists of tantalum globular particles which sizes vary from 8 to 40 nm. In the close vicinity to the interface copper grains contains a lot of microtwins bundles. Their formation plays a crucial role both in the microstructure evolution and fragmentation process of copper grains. Microhardness of copper-tantalum mixing zone is 2800 MPa which is 2 times higher than that of initial materials. The tensile test has shown the significant growth of composite yield strength in comparison with that of initial materials.