An enhanced unfolding Inverse Finite Element Method (IFEM) has been used together with an extended strain-based forming limit diagram (EFLD) to develop a fast and reliable approach to predict the feasibility of the deep drawing process of a part and determining where the failure or defects can occur. In the developed unfolding IFEM, the meshed part is properly fold out on the flat sheet and tre...

The expressions for the free energy in two recent formulations of strain gradient plasticity are extended to include the locked-in strain energy around statistically stored dislocations. This is accomplished by using the strain dependent factor h(ep), which represents the fraction of the rate of plastic work converted into heat in accordance with the latent heat measurements from classical meta...

Equal channel multi angular pressing (ECMAP) process is the efficient method to enhance the productivity of ultra-fine grained (UFG) materials, by increasing process continuity and as a result decreasing process required time. Comparing repetitive ECAP method, in the same period, the number of passes can be done by ECMAP. In this article, ECMAP of AL strips in two typical annealed and as receiv...

The problem of quasistatic evolution in small strain associative elastoplasticity is studied in the framework of the variational theory for rate-independent processes. Existence of solutions is proved through the use of incremental variational problems in spaces of functions with bounded deformation. This provides a new approximation result for the solutions of the quasistatic evolution problem...

the brass tubes with foam cores of alsi7sic3, alsi7sic3fe1 and alsi7sic3fe3 were produced as the crush-boxes with circle and square cross-section. then axial compressive behavior and energy absorption capability of the foam-filled tubes were investigated during the quasi-static progressive plastic buckling. the uniaxial compressive stress–strain curves of the foam-filled brass tubes exhibited t...

A 3-D finite element model is used to simulate water jet spot welding. The simulation is validated using the experimental data obtained by one of authors with other workers. The simulations identify parameters which correlate well with the quality of the welds produced. In particular the levels of equivalent plastic strain (PEEQ) and shear stress directions are shown to predict whether or not t...

Experimental assessment of the reverse algorithms that enable the extraction of plastic properties from the load–depth of penetration curves was conducted. Results show that they predict the stresses at 3.3% and 5.7% representative strains for Berkovich and 60 cone-equivalent three-sided pyramidal indenters, respectively, with good accuracy. It was shown that the uniaxial stress–strain curves c...