Effect of low temperature annealing on microstructure and properties of copper foil

Abstract

Electrodeposited copper foil has a non-equilibrium microstructure, and self-annealing takes place at room temperature. In this paper, the evolution of morphology, texture, and microstructure of copper foil during low-temperature annealing was analyzed. Then the microstructure and properties of copper foil deposited by a thickness of 6 µm electrodeposition were systematically studied. The annealing twin evolution behavior of ultra-thin lithium copper foil during annealing treatment is revealed. The production of twins and recrystallization of copper foil during low-temperature annealing is shown to be driven by the non-equilibrium structure and internal tension of the electrodeposited copper foil. The continual decrease in vacancy concentration is caused by an increase in annealing time. The conductivity of the copper foil is increased by 106.95 % percent by the twinning and the vacancy. The twin effect and altered grain size after annealing can reduce tensile strength by 11.55 % and increase elongation by almost 1.15 times.