Thin shell torispherical pressure vessel heads are known to exhibit complex elasticplastic deformation and buckling behaviour under static pressure. In pressure vessel Design by Analysis, the designer is required to assess both of these behaviour modes when specifying the allowable static load. The EN and ASME Boiler and Pressure Vessel Codes permit the use of inelastic analysis in design by an...

This paper provides an introduction in the field of severe plastic deformation (SPD). First of all the main methods to produce SPD materials are discussed. In the following section, the mechanisms leading to the formation of fine grains are reviewed and the influence of changes in strain path is highlighted. During post-SPD thermal annealing, some typical microstructural changes take place. The...

Thin shell torispherical pressure vessel heads are known to exhibit complex elasticplastic deformation and buckling behaviour under static pressure. In pressure vessel Design by Analysis, the designer is required to assess both of these behaviour modes when specifying the allowable static load. The EN and ASME Boiler and Pressure Vessel Codes permit the use of inelastic analysis in design by an...

The localization of plastic deformation into a shear band is discussed as an instability of -plastic flow and a precursor to rupture. Experimental observations are reviewed, a ge~eral theoretical framework is presented, and specific calculations of critical conditions are carried out for a variety of material models. The interplay between features of inelastic constitutive description~ especial...

BACKGROUND Metallic reconstruction plates used for fracture stabilization typically require intraoperative contouring for patient-specific anatomical fit. Despite this, characterization of plate mechanical properties after contouring has previously been limited. The objective of this study was to assess whether contouring affects fatigue resistance for three types of Stryker seven-hole stainles...

Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic...

the aim of the present study was to prepare an oral tablet from liquid yogurt by reforming the physical properties for easy transportation, long-term storage and also as a complementary dairy product in case of nutrient deficiency. the liquid fresh yogurt was lyophilized at -40°c and 0.03 mtor pressure. the dry powder was homogenized by a 12 mesh size sieve. some tests such as carr’s compressib...

severe plastic deformation (spd) methods were developed for producing of metals and alloys with ultrafine grained (ufg) microstructures having high strength. parallel tabular channel angular pressing (ptcap) as a noble severe plastic deformation (spd) method was used to produce ultrafine grained (ufg) and nanostructured cu-30%zn tubes. in this paper, the effect of ptcap process temperature on t...