The microstructure of WE93 alloy in different states and the mechanical properties at room temperature were investigated, and the creep behavior of the extruded and aged alloy at 200 ℃and at stress of 100, 125 and 15...The microstructure of WE93 alloy in different states and the mechanical properties at room temperature were investigated, and the creep behavior of the extruded and aged alloy at 200 ℃and at stress of 100, 125 and 150 MPa was also discussed. The result shows that the microstructure of as-cast WE93 alloy consists of α-Mg, Mg 12 （MM） and Mg 24 Y 5 with an average grain size of 45 μm. After being homogenized at 535 ℃for 18 h, the Mg 24 Y 5 phase is dissolved completely and there is only Mg 12 （MM） phase left around the grain boundaries. The grains do not grow up as prolonging the homogenization time. The extruded alloy has better mechanical properties than the as-cast alloy, especially the elongation increases to 12.5%. The extruded and aged alloy exhibits the highest yield strength and ultimate tensile strength of 315 and 385 MPa, respectively, however, the elongation decreases to 6.5%. The extruded and aged alloy exhibits good creep resistance at 200 ℃and at stress of 100 150 MPa. The creep stress exponent n is 2.97, suggesting that grain boundary sliding plays a dominant role at the corresponding temperature and applied stresses.展开更多
The hot working behaviors of Mg-9Y-1MM-0.6Zr （WE91） magnesium alloy were researched in a temperature range of 653 773 K and strain rate range of 0.001 1 s 1 on Gleeble 1500D hot simulator under the maximum deformati...The hot working behaviors of Mg-9Y-1MM-0.6Zr （WE91） magnesium alloy were researched in a temperature range of 653 773 K and strain rate range of 0.001 1 s 1 on Gleeble 1500D hot simulator under the maximum deformation degree of 60%. A mathematical model was established to predict the stress—strain curves of this alloy during deformation. The experimental results show that the relationship between stress and strain is obviously affected by the strain rates and deformation temperatures. The flow stress of WE91 magnesium alloy during high temperature deformation can be represented by Zener-Hollomon parameter in the hyperbolic Arrhenius-type equation, and the stress—strain curves obtained by the established model are in good agreement with the experimental results,which prove that the model reflects the real deformation characteristics of the WE91 alloy. The average deformation activation energy is 220 kJ/mol at strain of 0.1. The microstructures of WE91 during deformation processing are influenced by temperature and strain rates.展开更多
基金Projects(2007CB613704,2007CB613705)supported by the National Basic Research Program of China
文摘The microstructure of WE93 alloy in different states and the mechanical properties at room temperature were investigated, and the creep behavior of the extruded and aged alloy at 200 ℃and at stress of 100, 125 and 150 MPa was also discussed. The result shows that the microstructure of as-cast WE93 alloy consists of α-Mg, Mg 12 （MM） and Mg 24 Y 5 with an average grain size of 45 μm. After being homogenized at 535 ℃for 18 h, the Mg 24 Y 5 phase is dissolved completely and there is only Mg 12 （MM） phase left around the grain boundaries. The grains do not grow up as prolonging the homogenization time. The extruded alloy has better mechanical properties than the as-cast alloy, especially the elongation increases to 12.5%. The extruded and aged alloy exhibits the highest yield strength and ultimate tensile strength of 315 and 385 MPa, respectively, however, the elongation decreases to 6.5%. The extruded and aged alloy exhibits good creep resistance at 200 ℃and at stress of 100 150 MPa. The creep stress exponent n is 2.97, suggesting that grain boundary sliding plays a dominant role at the corresponding temperature and applied stresses.
基金Projects(2007CB613704,2007CB613705)supported by the National Basic Research Program of China
文摘The hot working behaviors of Mg-9Y-1MM-0.6Zr （WE91） magnesium alloy were researched in a temperature range of 653 773 K and strain rate range of 0.001 1 s 1 on Gleeble 1500D hot simulator under the maximum deformation degree of 60%. A mathematical model was established to predict the stress—strain curves of this alloy during deformation. The experimental results show that the relationship between stress and strain is obviously affected by the strain rates and deformation temperatures. The flow stress of WE91 magnesium alloy during high temperature deformation can be represented by Zener-Hollomon parameter in the hyperbolic Arrhenius-type equation, and the stress—strain curves obtained by the established model are in good agreement with the experimental results,which prove that the model reflects the real deformation characteristics of the WE91 alloy. The average deformation activation energy is 220 kJ/mol at strain of 0.1. The microstructures of WE91 during deformation processing are influenced by temperature and strain rates.
