Softened Microstructure and Properties of 12 μm Thick Rolled Copper Foil

Up to now, 12 μm thick rolled copper foil is the thinnest rolled copper foil that can be stably produced. The softened microstructure and properties of 12 μm thick rolled copper foil were systematically studied in this paper. The softened process consists of thermal treatment at 180 °C for different times. The results show that the softened annealing texture is mainly cubic texture, and the cubic texture fraction increases with the increase in annealing time. The cubic texture fraction reaches the highest (34.4%) after annealing for 60 min. After annealing for 1–5 min, the tensile strength and the bending times decrease significantly. After annealing for 10–60 min, the tensile strength tends to be stable, and the bending times increase slightly. With the increase in annealing time, the electrical conductivity increases gradually, reaching 92% International Annealed Copper Standard (IACS) after annealing for 60 min. Electrical conductivity can be used as a fast and effective method to analyze the microstructure of metals.