The influence of cryogenic treatment on the mechanical properties of the extruded Mg-Gd-Y-Zr(Mn) alloys was investigated by the tensile tests, scanning electron microscopy(SEM), transmission electron microscopy(TEM), ...The influence of cryogenic treatment on the mechanical properties of the extruded Mg-Gd-Y-Zr(Mn) alloys was investigated by the tensile tests, scanning electron microscopy(SEM), transmission electron microscopy(TEM), and energy dispersive X-ray spectroscopy (EDS). The results show that the mechanical properties of both alloys are improved greatly during the in situ tensile test by soaking the samples in liquid nitrogen for 10 min. The ultimate tensile strength, yield tensile strength and elongation of cryogenic treated magnesium alloy added with zirconium or manganese are largely elevated. And remarkable microstructure change is observed in both alloys by cryogenic treatment. There are a large number of twins,rod-like, tree-like and chrysanthemum-like precipitated phases in the microstructures and the fracture surfaces exhibit the characteristics of ductile rupture when they are observed at room temperature.展开更多
The microstructures and mechanical properties of Mg-9Gd-4Y-0.6Zr alloy were investigated. The results show that the ultimate tensile strengths of the extrusion-T5 temper of this alloy at -196,25, 250, 300 and 350℃are...The microstructures and mechanical properties of Mg-9Gd-4Y-0.6Zr alloy were investigated. The results show that the ultimate tensile strengths of the extrusion-T5 temper of this alloy at -196,25, 250, 300 and 350℃are as high as 521, 370, 348,262 and 150 MPa, respectively. It is noteworthy that 8% plasticity occurs at -196℃and 180% superplasticity occurs at 400℃. In the peak hardness of Cast-T5, Cast-T6, Ext-T5 and Ext-T6, the highest is that of Ext-T5. The prismatic precipitates providing an effective barrier to dislocation gliding on the basal plane are the cause of strengthening of this alloy. The plate-shaped precipitates formed on the prismatic planes provide the most effective barriers to the gliding dislocations, and they are the cause of strengthening of this alloy.展开更多
基金Project (51412020304QT7106) supported by the National Defense Pre-investigation Foundation of ChinaProject(2003AA741043) supported by the National High-Tech Research and Development Program of ChinaProject(5133001E) supported by the State Key Fundamental Research and Development Program of China
文摘The influence of cryogenic treatment on the mechanical properties of the extruded Mg-Gd-Y-Zr(Mn) alloys was investigated by the tensile tests, scanning electron microscopy(SEM), transmission electron microscopy(TEM), and energy dispersive X-ray spectroscopy (EDS). The results show that the mechanical properties of both alloys are improved greatly during the in situ tensile test by soaking the samples in liquid nitrogen for 10 min. The ultimate tensile strength, yield tensile strength and elongation of cryogenic treated magnesium alloy added with zirconium or manganese are largely elevated. And remarkable microstructure change is observed in both alloys by cryogenic treatment. There are a large number of twins,rod-like, tree-like and chrysanthemum-like precipitated phases in the microstructures and the fracture surfaces exhibit the characteristics of ductile rupture when they are observed at room temperature.
基金Project(51330) supported by the National Fundamental Research Program of China
文摘The microstructures and mechanical properties of Mg-9Gd-4Y-0.6Zr alloy were investigated. The results show that the ultimate tensile strengths of the extrusion-T5 temper of this alloy at -196,25, 250, 300 and 350℃are as high as 521, 370, 348,262 and 150 MPa, respectively. It is noteworthy that 8% plasticity occurs at -196℃and 180% superplasticity occurs at 400℃. In the peak hardness of Cast-T5, Cast-T6, Ext-T5 and Ext-T6, the highest is that of Ext-T5. The prismatic precipitates providing an effective barrier to dislocation gliding on the basal plane are the cause of strengthening of this alloy. The plate-shaped precipitates formed on the prismatic planes provide the most effective barriers to the gliding dislocations, and they are the cause of strengthening of this alloy.