Materials with ultrafine-grained structure and unique physical and mechanical properties can be obtained by methods of severe plastic deformation, which include processes of asymmetric rolling (AR). Asymmetric rolling is a very effective way to create ultrafine-grained structures of metals and alloys. Since the asymmetric rolling is a continuous process, it has great potential for industrial pr...

This paper deals with the possibility of reducing carbon content by heat treatment in reactive atmospheres in order to improve plastic deformations properties of steel sheets. The heat treatment involves a decarburation annealing after a cold rolling, as opposed to the traditional process that performs the heat treatment in non-reactive atmospheres. Some of the most relevant variables were stud...

The accumulation of litter in marine and coastal environments is a major threat to marine life. Data on marine litter in the gastrointestinal tract of stranded loggerhead turtles, Caretta caretta, found along the Portuguese continental coast was presented. Out of the 95 analysed loggerheads, litter was present in 56 individuals (59.0%) and most had less than 10 litter items (76.8%) and less tha...

Sheet specimens of aluminum alloy 5754 were deformed along a series of bi-linear, equal-biaxial and uniaxial, strain paths while simultaneously measuring stress–strain behavior. The Visco-Plastic Self-Consistent crystal plasticity model, which incorporates texture evolution, was used to simulate the flow stress and hardening behavior based in part on the measured crystallographic texture before...

Cropping is a cutting process whereby opposing aligned blades create a shearing failure by exerting opposing forces normal to the surfaces of a metal sheet or plate. Building on recent efforts to quantify cropping, this paper formulates a plane strain elastic–plastic model of a plate subject to shearing action by opposing rigid platens. Shear failure at the local level is modeled by a cohesive ...

Jerzy Kanicki Shu-Jen Lee Yongtaek Hong Chia-Chen Su Abstract — The optoelectronic properties of red, green, and blue poly(fluorene) co-polymer lightemitting devices (PLEDs) on a plastic substrate having a multi-layered structure with water vapor and oxygen transmission rates of less than 10–5 g/cm2-day-atm and 10–7 cc/cm2-day-atm, respectively, is reported. A semitransparent thin metal multi-l...

SIJMMARY BY USING a simplified constitutive model of a pointed vertex on subsequent yield loci, namely, such that the equations of deformation-theory of rigid-plastic solids apply for fully-active stress increments, the onset of localized necking under biaxial stretching has been predicted. The predictions agree reasonably well with reported experimental observations. Since localized necking un...

The Finite Element analysis of the elastic-plastic behavior is of fundamental importance in automobile industry. To predict accurately the final geometry of the structure and the distribution of strain and stress, accurate integration of the constitutive laws over the strain path is essential. Our objective in this paper is to develop an effective and accurate stress integration scheme for the ...