Organosilyl groups were successfully incorporated in AFI and VFI aluminophosphate frameworks using organoalkoxysilanes to modify hydrophobicity and acidity of the molecular sieves.

The elasto-plasticity behavior of a high-strength steel sheet of 980 MPa-TS was investigated by performing biaxial tension experiments. In order to evaluate the accuracy of constitutive models of plasticity in describing such elasto-plasticity behavior, numerical simulations of stressstrain responses were conducted for the same stress paths as those in the experiments using two types of constitutive models: the isotropic hardening model (IH model) and the kinematic hardening model proposed by the present authors (Yoshida-Uemori model). In this work, special emphasis is placed in the cases of stress-path change. In experiments on radial loadings after equi-balanced tension preloading, it was found that flow stresses are considerably lower than uniaxial tension flow stress. The IH model can hardly describe this phenomenon, although it is sufficient for stress-strain analysis of proportional loading cases. In contrast to this, the Yoshida-Uemori model can well predict every stressstrain response in biaxial stress-path changes.

This paper deals with plastic deformations of a high tensile strength steel sheet (HTSS sheet) under biaxial stress condition including strain path. Using a cruciform specimen of a HTSS sheet of 780MPa-TS, experiments under proportional and non-proportional loadings were investigated. Numerical simulations of stress-strain responses for several strain paths after biaxial stretching were conducted using a large-strain cyclic plasticity model (Yoshida-Uemori model). The results of numerical simulation agrees well the corresponding experimental results, which is attributed to the accurate modeling of the backstress evolution of the anisotropic yield function.

The elastopasticity behavior of a high-strength steel sheet was investigated by performing biaxial tension experiments. To evaluate the accuracy of constitutive models in describing such elastoplasticity behavior, numerical simulations of stress-strain responses were conducted for the same stress paths as those in the experiments using two types of models: the isotropic hardening model (IH model) and the kinematic hardening model proposed by the present authors (Yoshida-Uemori model). In this work, special emphasise is placed in the cases of stress-path change. In experiments on radial loadings after equibalanced tension preloading, it was found that flow stresses are considerably lower than uniaxial tension flow stress. The IH model hardly describes this phenomenon, although it is sufficient for stress-strain analysis of proportional loading cases. In contrast, the Yoshida-Uemori model can well predict every stress-strain response in biaxial stress-path changes.

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