摘要
The hot deformation behavior of mechanically alloyed (MA鈥檈d) Al6063/0.75Al2O3/0.75Y2O3 nano-composite was characterized in the temperature and strain rate ranges of 300-500 掳C and 0.001-1 s鈭? using compression test. Hot workability is interpreted by processing maps based on dynamic material modeling (DMM) and constitutive model was established based on sine-hyperbolic Arrhenius kinetic rate equation. Dynamic recrystallization (DRX) occurs in the temperature range of 400-500 掳C and strain rate range of 0.001-0.1 s鈭?. The optimum processing parameters for hot working of MA鈥檈d Al6063/0.75Al2O3/0.75Y2O3 nano-composite was identified to be in two domains, viz.: (i) T = 395-440 掳C and and (ii) T = 440-500 掳C and respectively with maximum efficiency of about 37-39%respectively. At strain rates ranging from 0.1 to 1 s鈭? the nano-composite exhibits flow instability for all temperatures investigated. The average apparent activation energy for hot deformation is calculated to be 181 kJ/mol and flow behavior of the material was styled through a constitutive model. The reasons for the flow instability have been observed to be the surface cracking, void formation, matrix cracking, pores and wedge cracking.