The mechanical behavior of a single phase (fcc) Al0.3CoCrFeNi high-entropy alloy (HEA) was studied in the low and high strain-rate regimes. The combination of multiple strengthening mechanisms such as solid solution hardening, forest dislocation hardening, as well as mechanical twinning leads to a high work hardening rate, which is significantly larger than that for Al and is retained in the dy...

Linear polypropylene (PP)—composed of long polymer chains devoid of branches or crosslinked structure—and blends of PP with olefinic elastomers are widely used in the automotive and packaging industries. What makes foams produced with these materials of growing interest is their potential to replace the prevalent thermoset polyurethane foams which are not recyclable. However, the production of ...

Thermal treatments and thermo-mechanical processing routes were applied on a conventional structural steel (st37 steel: 0.12C-1.11Mn-0.16Si) for improvement of tensile properties and enhancement of work-hardening behavior. Full annealing resulted in a sheet with coarse ferrite grains and pearlite colonies arranged alternatively in distinct bands, which showed high ductility, low strength, and t...

This paper presents the application of a life fraction hardening rule to the analytical calculation of creep in hot section components. Accurate prediction of creep is critical to assuring the mechanical integrity of heavy-duty, industrial gas turbine (IGT) hardware. The accuracy of such predictions depend upon both the creep models assumed and how those models are implemented in a finite eleme...

Simulations are used to examine the microscopic origins of strain hardening in polymer glasses. While traditional entropic network models can be fit to the total stress, their underlying assumptions are inconsistent with simulation results. There is a substantial energetic contribution to the stress that rises rapidly as segments between entanglements are pulled taut. The thermal component of s...

The effects of entanglement and chain orientation on strain hardening in glassy polymers are separated by examining mixtures of chains with different lengths. Simulations show that the orientation of a molecule of a given chain length is the same in monodisperse systems and bidisperse mixtures, even when entangled and unentangled chains are mixed. In addition, the stress in mixtures is equal to...

The critical fluid-shear stress for the onset of sediment transport, θc, varies with history applied shear. This effect has been primarily attributed to compaction; role shear jamming is less explored. We examine response a granular bed cycles varying magnitude and direction, determine isotropic anisotropic contributions. Creep bed-load transport result in direction-dependent strain hardening θ...

We present in situ transmission electron microscope tensile tests on focused ion beam fabricated single and multiple slip oriented Cu tensile samples with thicknesses in the range of 100-200 nm. Both crystal orientations fail by localized shear. While failure occurs after a few percent plastic strain and limited hardening in the single slip case, the multiple slip samples exhibit extended homog...

advanced high strength steels (ahss) have recently attracted great attention because of their superior mechanical properties. a modern group of these steels, known as twinning induced plasticity (twip) steels, shows a unique combination of strength and ductility even at high rates of strain. in order to examine the functionality of such steels in dynamic loading conditions, their mechanical beh...

This paper presents a summary of the new semi-analytical integration method presented in [10] for von Mises elastoplasticity model with combined linear isotropic-kinematic hardening within a small deformation range. Solutions for the case of constant strain rate and constant stress rate assumptions are also presented. Furthemore, it is shown how the general solution reduces to the particular ca...