Local damage models are known to produce pathological mesh dependence in finite element simulations. The solution is to either use a regularization technique or to adopt a non-local damage model. Viscoplasticity is one technique which can regularize the mesh dependence of local damage model by incorporating a physical phenomenon in the constitutive model i.e. rate effects. A detailed numerical ...

We have used the Mori–Tanaka method to study the effect of nonlinear interface debonding on the constitutive behavior of composite material with high particle volume fraction. The interface debonding is characterized by a nonlinear cohesive law determined from the fracture test of the high explosive PBX 9501. Using the example of the composite material with spherical particles subject to hydros...

The coupled nonlinear partial differential equations governing the thermomechanical and axisymmetric deformations, of a cylindrical rod penetrating into a thick target, also made of a rigid/viscoplastic material, are solved by the finite element method. It is assumed that the deformations of the target and the penetrator as seen by an observer situated at the stagnation point and moving with it...

The Bauschinger effect (BE) in single crystals of Hadfield manganese steel (Fe, 12.3Mn, 1.0C in wt pct) was studied for three crystallographic orientations, [111], [123], and [001]. Both forward tensionreverse compression (FT/RC) and forward compression-reverse tension (FC/RT) loading schemes were used to investigate the role of deformation history on the BE. The evolution of stress-strain resp...

We experimentally demonstrate an exploitation of the nonlinear softening, hardening, and veering phenomena (near crossing), where the frequencies of two vibration modes get close to each other, to realize a bandpass filter of sharp roll off from the passband to the stopband. The concept is demonstrated based on an electrothermally tuned and electrostatically driven MEMS arch resonator operated ...

The damping characteristics of Ti50Ni50-xCux (x = 0~30 at.%) shape memory alloys (SMAs) at a low frequency have been studied using a dynamic mechanical analyzer. The magnitude of the tan δ value and the values of the storage modulus (E₀) softening/hardening and the strain variation exhibited in B2↔B19 transformation are all higher than those in B2↔B19' transformation. The larger E₀ softening/ha...

In this study, a Ti–33Zr–12Al–6V alloy was prepared, and its work hardening softening mechanisms were investigated via tensile tests conducted at room temperature. The interaction between the dislocations strain-induced martensite (SIM) results in hardening; whereas, shearing of grain boundaries by for entering adjacent grains softening, which occurs when logarithmic strains is 5.8% 7.6%. Work ...