Microstructure and mechanical properties of Cu/Al/Cu clad strip processed by the powder-in-tube method

A Cu/Al/Cu clad strip was produced successfully by the powder-in-tube method. The interface morphology, element distribution, peeling strength and tensile strength of the clad strips after annealing and further cold rolling were investigated. The experimental results indicate that the diffusional width of the intermetallic layer will increase with the annealing temperature, but the average peeling strength of the Cu/Al/Cu clad strip rises first and then falls. Further cold rolling process can significantly reduce the thickness of the intermetallic layer and improve the average peeling strength of the Cu/Al/Cu clad strip except for those annealed at 550 °C. There exists an optimal diffusional thickness (approximately 15.4 μm) for the annealed Cu/Al/Cu clad strip processed by the powder-in-tube method. The clad strips annealed at 450 °C and further cold rolled to 0.5 mm can obtain the best mechanical performance, the peeling strength, ultimate tensile strength and elongation are 17.8 N/mm, 286 MPa and 9.4%, respectively. The peeling surfaces, peeling tests and tensile tests prove that compact and uniform intermetallic compounds can provide excellent performance for Cu/Al/Cu clad strips.

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