Microstructure and mechanical properties investigations of copper-steel composite fabricated by explosive welding

This paper presented a systematic study of microstructure and mechanical properties of Cu/Fe explosive-bonded interfaces. The periodic wavy bonding structure with both vortex region and solid-solid bonding region was embedded in the interface. Typical annealing twin structures were observed in the texture and orientation analysis of Cu matrix. The ASBs filled with some much smaller size equiaxed grains and orientation variations in different areas were found in the Fe matrix. The transition layer consisted of nano-sized grains of 60 nm was formed between the copper and steel plate. The microindentation results showed that the hardness of the interface (330.9 MPa) and deformation area (Cu 100 HV and Fe 286.8 HV) was higher than the matrix regions. The higher hardness of the transition layer (15.707 GPa) determined by nanoindentation analysis was explained by the existence of nanocrystallines in this zone. The induced tensile tests showed that the cracks didn’t extent along the interface wave structure but inside the copper matrix, reflecting the high quality of the bonding. [Display omitted] •Copper-steel composite plates were successfully fabricated by explosive welding.•Microstructure in the interface was investigated.•The texture and orientation analysis of the interface was carried out by EBSD.•Nanoindentation tests were performed to determine mechanical properties in transition layer.