A study on the prediction of springback angle is presented, with focus on the straight flanging operation. The objective is to evaluate the reliability of different ways of prediction. An experiment of straight flanging operation is conducted. Major prediction approaches such as analytical model, numerical simulation using Finite Element Method (FEM) and Meshfree Method are discussed. A set of ...

Helium implantation at room temperature was performed to investigate irradiation hardening of ferritic/martensitic steels. Bulk hardness was extracted from Nix-Gao model using a Berkovich nano-indentor. The correlation between irradiation hardening and helium concentration ranging 500 2000 appm was examined. Nano-hardness increases as a function of helium concentration. The hardening of Fe is s...

The quasistatic rate-independent evolution of the Prager-Zieglertype model of linearized plasticity with hardening is shown to converge to the rate-independent evolution of the Prandtl-Reuss elastic/perfectly plastic model. Based on the concept of energetic solutions we study the convergence of the solutions in the limit for hardening coe cients converging to 0 by using the abstract method of Γ...

Force flexibility is often referred to when considering the effectiveness of a force. Flexibility is all too often loosely defined and illcommunicated due to the number of factors involved and the nature of the English language. During the Army Experimental Framework Experiment Headline 2006 a key variable in determining a forces ability to continue its mission was the flexibility of the force ...

This paper deals with investigating the nonlinear oscillation of carbon nanotube manufactured nano-resonator. The governing equation nano-resonator is extracted in context nonlocal elasticity. impact Casimir force also incorporated developed model. A closed-form solution based on energy balance method presented for oscillations proposed compared numerical solution. influential parameters includ...

Metallic nanowires usually exhibit ultrahigh strength but low tensile ductility owing to their limited strain hardening capability. Here we study the unique strain hardening behavior of the five-fold twinned Ag nanowires by nanomechanical testing and atomistic modeling. In situ tensile tests within a scanning electron microscope revealed strong strain hardening behavior of the five-fold twinned...

Micromechanical experiments, image analysis, and theoretical modeling revealed that local failure events and compressive stresses of vertically aligned carbon nanotubes (VACNTs) were uniquely linked to relative density gradients. Edge detection analysis of systematically obtained scanning electron micrographs was used to quantify a microstructural figure-of-merit related to relative local densi...

The direct parametrisation method for invariant manifolds is a nonlinear reduction technique which derives mappings and reduced-order dynamics that describe the evolution of dynamical systems along low-dimensional invariant-based span phase space. It can be directly applied to finite element problems. When development performed using an arbitrary order asymptotic expansion, it provides efficien...

In ichnology, the Goldilocks effect describes a scenario in which a substrate must be 'just right' in order for tracks to form-too soft, the animal will be unable to traverse the area, and too firm, the substrate will not deform. Any given substrate can therefore only preserve a range of tracks from those animals which exert an underfoot pressure at approximately the yield strength of the sedim...

Recently, spin excitations in doped cuprates have been measured using resonant inelastic x-ray scattering. The paramagnon dispersions show the large hardening effect in the electron-doped systems and seemingly doping independence in the hole-doped systems, with the energy scales comparable to that of the antiferromagnetic (AFM) magnons. This anomalous hardening effect and the lack of softening ...