The role of local intensive heating on microstructure of 2024Al/Al18B4O33w composite deformed with strain rate >0.01 s−1

Highlights: • The addition of the Al₁₈B₄O₃₃w leads to the lower rate sensitivity exponent of the composite. • Local intensive heating is favorable to dislocation motion resulting in the lower calculated activation energy of 2024Al/Al₁₈B₄O₃₃w composite compared with that of unreinforced 2024Al. • The locally intensive adiabatic heating benefits the occurrence of dynamic recovery and dynamic recrystallization. -- Abstract: The relationship among local intensive heating, activation energy and corresponding microstructures of 2024Al/Al₁₈B₄O₃₃w composite during hot deformation are studied. The results show that 2024Al/Al₁₈B₄O₃₃w composite exhibits strain rate sensitivity. The addition of Al₁₈B₄O₃₃w leads to the lower rate sensitivity exponent of 2024Al/Al₁₈B₄O₃₃w 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/Al₁₈B₄O₃₃w composite than that of unreinforced 2024Al. Meantime, locally intensive heating benefits the occurrence of dynamic recovery and dynamic recrystallization.