Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stre...Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stress 2 MPa has been demonstrated. It was shown through optical microstructure that the average grain sizes at gauge length section before and after superplastic tension and at grip section were 7.5 mu m, 31.7 mu m and 20 mu m respectively, indicating significant deformation induced grain growth and static grain growth. Comparison of experiment data with published data for superplastic Mg-Li alloys shows that fine grain size and about 50 to 50 phase ratio contribute to achieving the largest superplasticity. Some related research works in other alloys are compiled and further evidences to such theoretic argument are provided.展开更多
This paper studied the fractal characteristic of the interfacial shear surface of steel-Al solid to liquid bonding plate, and determined the relationship between fractal dimension and interfacial shear strength. The r...This paper studied the fractal characteristic of the interfacial shear surface of steel-Al solid to liquid bonding plate, and determined the relationship between fractal dimension and interfacial shear strength. The research results showed that the relationship between fractal dimension and interfacial shear strength could be described as y=26.2x+4.2 (where y was interfacial shear strength, x was fractal dimension) and when 08Al steel plate was coarsened by steel wire wheel which was made up with steel wires whose diameter were 1.4 similar to 1.6 mm, the optimum coarsening pattern of the steel plate surface could be got, the corresponding maximum interfacial shear surface fractal dimension of the bonding plate was 2.33, and the maximum interfacial shear strength of the bonding plate was 65.3 MPa.展开更多
基金Ph.D fund of China National Education Commission !project number9314515
文摘Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stress 2 MPa has been demonstrated. It was shown through optical microstructure that the average grain sizes at gauge length section before and after superplastic tension and at grip section were 7.5 mu m, 31.7 mu m and 20 mu m respectively, indicating significant deformation induced grain growth and static grain growth. Comparison of experiment data with published data for superplastic Mg-Li alloys shows that fine grain size and about 50 to 50 phase ratio contribute to achieving the largest superplasticity. Some related research works in other alloys are compiled and further evidences to such theoretic argument are provided.
文摘This paper studied the fractal characteristic of the interfacial shear surface of steel-Al solid to liquid bonding plate, and determined the relationship between fractal dimension and interfacial shear strength. The research results showed that the relationship between fractal dimension and interfacial shear strength could be described as y=26.2x+4.2 (where y was interfacial shear strength, x was fractal dimension) and when 08Al steel plate was coarsened by steel wire wheel which was made up with steel wires whose diameter were 1.4 similar to 1.6 mm, the optimum coarsening pattern of the steel plate surface could be got, the corresponding maximum interfacial shear surface fractal dimension of the bonding plate was 2.33, and the maximum interfacial shear strength of the bonding plate was 65.3 MPa.
