In consideration of superplastic deformation being highly sensitive to structure, superplastic bulging constitutive equations with varying m values are given for the first time by solving the differential equation tha...In consideration of superplastic deformation being highly sensitive to structure, superplastic bulging constitutive equations with varying m values are given for the first time by solving the differential equation that defines m values with the function simulation method according to the m-log curve in the biaxial tensile stress state. The constitutive equation established by simulating the m-log curve with negative power functions can not only exhibit the characteristics of varying m values, but also express either by or by . The equation contains three constants,~mm, ~mk and η, and the larger the ~mm and η, the nearer the ~mm/m^k to unity, and the better the material’s superplasticity. So superplastic bulging indexes of materials are related with the shape of the m-log curve, which can explain why mere ~mm measured at theuniaxial tension is unable to describe the law of superplastic bulging and express the superplastic bulging indexes of materials singly. Superplastic bulging constitutive展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘In consideration of superplastic deformation being highly sensitive to structure, superplastic bulging constitutive equations with varying m values are given for the first time by solving the differential equation that defines m values with the function simulation method according to the m-log curve in the biaxial tensile stress state. The constitutive equation established by simulating the m-log curve with negative power functions can not only exhibit the characteristics of varying m values, but also express either by or by . The equation contains three constants,~mm, ~mk and η, and the larger the ~mm and η, the nearer the ~mm/m^k to unity, and the better the material’s superplasticity. So superplastic bulging indexes of materials are related with the shape of the m-log curve, which can explain why mere ~mm measured at theuniaxial tension is unable to describe the law of superplastic bulging and express the superplastic bulging indexes of materials singly. Superplastic bulging constitutive
