Effect of electric current on formability and microstructure evolution of Cu/Al laminated composite

Cu/Al laminated composite is a kind of material with wide application value, which has attracted the interest of many researchers. Improving the formability of Cu/Al laminated composite is a hot research topic. Electrically assisted manufacturing technology can improve the formability of metal materials, and its application to Cu/Al laminated composite plate is anticipated to improve its formability. In this work, the mechanical properties of Cu/Al laminated composite during electrically assisted (EA) tension were studied, and the effect of electric current on the microstructure evolution of Cu/Al laminated composite was characterized. The results showed that the forming force of Cu/Al laminated composite decreased significantly with the increase of current when the frequency is constant, but the forming limit decreased. The reason was that the increase in current density led to local overheating, which eventually led to premature fracture of the specimen. Under low frequency conditions, the elongation of Cu/Al laminated composite decreased moderately, but the forming force decreased obviously. The microstructure characterization results showed that the electric current circulated only in the Cu matrix during the EA tension. The electric current lowered the dislocation density of Cu layer and promoted dislocation unwinding. The proportion of recrystallized grains in the Cu layer increased slightly under the action of current. In addition, the current accelerated the change of texture type of Cu layer and the texture strength decreased.