The effect of rolling conditions on the strength and microstructure of dispersion strengthened copper strips

The effect of rolling conditions on the strength and microstructure of alumina dispersed copper strips was investigated. Commercial strips, Glidcop Al-25, were rolled to similar total reductions by one or multiple passes at room temperature or at 540°C. The specimens rolled at room temperature (cold rolled specimens) had higher strength and hardness than those rolled at 540°C (warm rolled specimen), when rolling schedules were the same. The strength and hardness of the cold rolled specimens were little influenced by the number of rolling passes, whereas the multi-pass warm rolled specimen had lower strength and hardness and higher elongation than the single-pass warm rolled specimen. The structure of specimens is characterized by banded substructures and their strength could be expressed as a function of the band size. In warm rolled strips, no dynamic recrystallization occurred, but the band growth was observed.