The role of local intensive heating on microstructure of 2024Al/Al(18)B(4)O(33)w composite deformed with strain rate > 0.01 s(-1)

摘要

The relationship among local intensive heating, activation energy and corresponding microstructures of 2024Al/Al(18)B(4)O(33)w composite during hot deformation are studied. The results show that 2024Al/Al(18)B(4)O(33)w composite exhibits strain rate sensitivity. The addition of Al(18)B(4)O(33)w leads to the lower rate sensitivity exponent of 2024Al/Al(18)B(4)O(33)w composite. The inhomogeneous deformation induces local intensive heating, resulting in rise of the related local temperature. Local temperature rise favorable to dislocation motion results in the lower calculated activation energy of 2024Al/Al(18)B(4)O(33)w composite than that of unreinforced 2024Al. Meantime, locally intensive heating benefits the occurrence of dynamic recovery and dynamic recrystallization.