The behavior evolvement of Mg-7.22Gd-4.84Y-1.26Nd-0.58Zr（GWN751K） magnesium alloy during the hot deformation process was discussed.The flow stress behavior of the magnesium alloy over the strain rate range of 0.002 ...The behavior evolvement of Mg-7.22Gd-4.84Y-1.26Nd-0.58Zr（GWN751K） magnesium alloy during the hot deformation process was discussed.The flow stress behavior of the magnesium alloy over the strain rate range of 0.002 to 2.000 s^-1 and in the temperature range of 623 to 773 K was studied on a Gleeble-1500D hot simulator under the maximum deformation degree of 60%.The experimental results showed that the relationship between stress and strain was obviously affected by strain rate and deformation temperature.The flow stress of GWN751K magnesium alloy during high temperature deformation could be represented by the Zener-Hollomon parameter in the hyperbolic Arrhenius-type equation.The stress exponent n and deformation activation energy Q were evaluated by linear regression analysis.The stress exponent n was fitted to be 3.16.The hot deformation activation energy of the alloy during hot deformation was 230.03 kJ/mol.The microstructures of hot deformation were also influenced by strain rate and compression temperature strongly.It was found that the alloy could be extruded at 723 K with the mechanical properties of σ0.2 = 260 MPa,σb = 320 MPa,and δ = 18%.展开更多
The behavior evolvement of Mg-9Y-1MM-0.6Zr （WE91） alloy during hot deformation process was discussed. The flow stress behavior of magnesium alloy over the strain rate range of 0.001 to 1 s–1 and the temperature ran...The behavior evolvement of Mg-9Y-1MM-0.6Zr （WE91） alloy during hot deformation process was discussed. The flow stress behavior of magnesium alloy over the strain rate range of 0.001 to 1 s–1 and the temperature range of 653 to 773 K was studied on a Gleeble-1500D hot simulator under the maximum deformation degree of 60%. The experimental results showed that the relationship between stress and strain was obviously affected by the strain rate and deformation temperature and the flow curves observed were typical of the occurrence of dynamic recrystallization. The flow stress of WE91 magnesium alloy during high temperature deformation could be represented by the Zener-Hollomon parameter in the hyperbolic Arrhenius-type equation. The average deformation activation energy Q and strain coefficient n were 224.11 kJ/mol and 3.08 by calculation,respectively. The processing maps were calculated and analyzed according to the dynamic materials model. The map at strain of 0.916 exhibited three domains with peak efficiency of 49%,44% and 42%,respectively. It was found that the alloy could be extruded at 693 K with mechanical properties of σ0.2=240 MPa,σb=315 MPa and δ=15.5%.展开更多
基金supported by the National Key Basic Research and Development Program (Nos.2 007CB613704 and 2007CB613705)
文摘The behavior evolvement of Mg-7.22Gd-4.84Y-1.26Nd-0.58Zr（GWN751K） magnesium alloy during the hot deformation process was discussed.The flow stress behavior of the magnesium alloy over the strain rate range of 0.002 to 2.000 s^-1 and in the temperature range of 623 to 773 K was studied on a Gleeble-1500D hot simulator under the maximum deformation degree of 60%.The experimental results showed that the relationship between stress and strain was obviously affected by strain rate and deformation temperature.The flow stress of GWN751K magnesium alloy during high temperature deformation could be represented by the Zener-Hollomon parameter in the hyperbolic Arrhenius-type equation.The stress exponent n and deformation activation energy Q were evaluated by linear regression analysis.The stress exponent n was fitted to be 3.16.The hot deformation activation energy of the alloy during hot deformation was 230.03 kJ/mol.The microstructures of hot deformation were also influenced by strain rate and compression temperature strongly.It was found that the alloy could be extruded at 723 K with the mechanical properties of σ0.2 = 260 MPa,σb = 320 MPa,and δ = 18%.
基金Project supported by the 973-National Key Basic Research Program (2007CB613704 and 2007CB613705)
文摘The behavior evolvement of Mg-9Y-1MM-0.6Zr （WE91） alloy during hot deformation process was discussed. The flow stress behavior of magnesium alloy over the strain rate range of 0.001 to 1 s–1 and the temperature range of 653 to 773 K was studied on a Gleeble-1500D hot simulator under the maximum deformation degree of 60%. The experimental results showed that the relationship between stress and strain was obviously affected by the strain rate and deformation temperature and the flow curves observed were typical of the occurrence of dynamic recrystallization. The flow stress of WE91 magnesium alloy during high temperature deformation could be represented by the Zener-Hollomon parameter in the hyperbolic Arrhenius-type equation. The average deformation activation energy Q and strain coefficient n were 224.11 kJ/mol and 3.08 by calculation,respectively. The processing maps were calculated and analyzed according to the dynamic materials model. The map at strain of 0.916 exhibited three domains with peak efficiency of 49%,44% and 42%,respectively. It was found that the alloy could be extruded at 693 K with mechanical properties of σ0.2=240 MPa,σb=315 MPa and δ=15.5%.
