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We have combined electrochemical, rheological and light scattering measurements to investigate the viscoelastic character of solutions of (2,4-bis (2-ethylhexylureido) toluene) (EHUT) in toluene in the presence of two ionic liquids: (trihexyl (tetradecyl) phosphonium hexafluorophosphate "Cyphos 110") and (tris(pentafluoroethyl) trifluorophosphate "aph4-cph12") used to substantially increase the solution conductivity required for the electrochemical study. The heterogeneous rate constant k 0 of the Fc/Fc + redox couple, the diffusivity (DFc), and the equivalent capacitance values of the double layer were measured in the presence and in the absence of EHUT. For Cyphos 110, the viscosity of solutions increases in the presence of EHUT, but the diffusion current exhibited no fluctuations. By opposition, for aph4-cph12, strong fluctuations of the diffusion current allowed to assign a viscoelastic character to the solutions when EHUT is added. Rheological and light scattering measurements revealed that the two ionic liquids act as chain stoppers for EHUT supramolecular chains. However, aph4-cph12 maintains the viscoelastic character of the EHUT solution whereas Cyphos 110 destroys the supramolecular structure.

The comprehension of the anisotropy impacts on mechanical properties of the rolled steel sheets was investigated using a non-quadratic anisotropic yield function. In this study, experimental and modelling determination of behavior of an industrial rolled sheets for a DIN 1623 St14 steel were carried out. The yield stresses and Lankford r-values in uniaxial were experimentally determined but the balanced biaxial tension stress states and rb were assumed. The parameters of the associated yield equation, derived from the three orthotropic yield functions proposed by Hill48 and Yld2000-2d, were determined. Predictions and the evolution of normalized yield stress and normalized Lankford parameters (plastic strain ratio) obtained by the presented investigative are considered. In order to describe the path of equivalent plastic behavior, the isotropic hardening function is described using the following various empirical standard formulae based on: Hollomon, Ludwick, Swift and Voce model.