Effect of TiB2 particles on the thermal deformation and recrystallization behaviour of Al-Cu-Mg alloys

To reveal the influence of TiB₂ particles on the thermal deformation behavior of Al-Cu-Mg alloys, thermal compression experiments were conducted in the temperature range of 340 to 500 °C, the strain rate range of 0.01 to 10 s⁻¹. Arrhenius-type constitutive equations were formulated to characterize the flow behavior of the alloys, and the microstructures of the deformed alloys were analyzed. The results indicate that TiB₂ particles markedly refine the grains of Al-Cu-Mg alloys from 117 to 35 µm (0.1 wt% TiB₂) and 29 µm (1 wt% TiB₂). Both the reduction of grain size and the presence of TiB₂ particles contribute to an increased flow stress during thermal deformation. And the grain refinement induced by the addition of TiB₂ particles enhances dynamic recrystallization processes. The excess TiB₂ particles (1 wt% TiB₂) further stimulate dynamic recrystallization via the particle-stimulated nucleation mechanism. Moreover, the addition of TiB₂ particles effectively suppresses the coarsening of recrystallized grains in Al-Cu-Mg alloys following thermal deformation.