MSID of monodisperse melts . The effect of the number of MD steps between each growth step is studied. A larger value of leads to better equilibrated systems, which MSID fits nicely with FPO and the target function of Auhl et al. (Ref. 13).
Principle of the two techniques used in this paper. From left to right: (i) homogeneous deformation uniaxial, (ii) homogeneous deformation triaxial, (iii) boundary driven deformation uniaxial, and (iv) boundary driven deformation triaxial.
Concentration profile of the sample deduced from layer analysis: The (gauge length) is defined as the distance between the two inflexion points of the working zone beads concentration profile.
Stress-strain curves (boundary driven deformation uniaxial tensile tests) at using various spring stiffness; is the ratio of the spring stiffness over the sample stiffness. The line is the viral stress divided by the working zone volume [Eq. (8)]. Points correspond to stress computed by the spring length. Both techniques lead to similar results.
Boundary driven deformation: Distance between upper and lower grips center of mass (COM) vs time. Secondary axes: Time averaged velocity of upper grip COM with respect to lower grip COM and target velocity . The mean velocity is very close to the target velocity, thus validating the uniaxial tensile technique.
High speed (drawing velocity of ) tensile test: triaxial tensile test applied to a glassy specimen by using different methods; the mechanical responses are very different. Snapshots at a strain of show that homogenous deformation (right) results in an unphysical ductile behavior compared to the localized deformation when grips are used (left), which is more realistic.
Stress-strain curves of uniaxial tensile test plotted vs true strain (upper axis) and (lower axis). The strain hardening regime is fitted linearly by the Gaussian expression [Eq. (9)] of strain hardening, ,
Behavior curves of uniaxial tensile test glassy and rubbery specimen. A zoom of the yield region is shown in the inset. No significant differences can be observed. The two snapshots correspond to a true strain of 1.5 at .
Stress-strain curves in a triaxial tensile test for a glassy sample (left) and rubbery specimen (right). The inset shows a zoom in the vicinity of yield. In both cases the agreement is remarkable between boundary driven and homogeneous deformation techniques. The snapshots correspond to a true strain of 1.5.
Some mechanical properties measured all stress-strain curves. Uncertainties represent the variations observed for six different samples. Bound. dri.: boundary driven tests. Homog. def.: homogenously deformed tests.
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