The ductility and plastic flow behavior of highly aligned nanotwinned copper produced by interrupted magnetron sputtering is investigated. Tensile tests were performed at various strain rates at both room and liquid nitrogen (77 K) temperatures. Higher ductility and strength are reported for all samples tested at 77 K. The observed inhomogeneous deformation and shear band propagation are discus...

Ambient and cryogenic surface mechanical attrition treatments (SMAT) are applied to bcc iron plate. Both processes result in significant surface grain refinement down to the ultrafine-grained regime; the cryogenic treatment results in a 45% greater grain size reduction. However, the refined region is shallower in the cryogenic SMAT process. The tensile ductility of the grain size gradient remai...

The influence of alloy composition of lowmelting Sn-Bi-Cu lead-free solder alloys on mechanical properties and solder joint reliabilities were investigated. The mechanically optimum alloy composition is Sn-40Bi-0.1Cu (mass%). The addition of 40mass%Bi improves the ductility and restrains the fillet-lifting, which are problems of lead-free solders with Bi. The addition of copper improves both th...

Shear bands generally initiate strain softening and result in low ductility of metallic glasses. In this Letter, we report high-resolution electron microscope observations of shear bands in a ductile metallic glass. Strain softening caused by localized shearing was found to be effectively prevented by nanocrystallization that is in situ produced by plastic flow within the shear bands, leading t...

The microstructure and tension ductility of a series of Ti-based bulk metallic glass matrix composite (BMGMC) is investigated by changing content of the β stabilizing element vanadium while holding the volume fraction of dendritic phase constant. The ability to change only one variable in these novel composites has previously been difficult, leading to uninvestigated areas regarding how composi...

in the present study, mechanical properties and low cycle fatigue behavior of a solid-solutionized aa6061 aluminum alloy produced by equal channel angular pressing (ecap) process were investigated. the grain refinement after two passes of ecap significantly increased the yield stress and ultimate tensile stress and decreased the ductility of the alloy. however, the improvement of low cycle fati...

Ductility demand during an earthquake has long been known to be a good measure of structural damage in buildings during earthquakes. For design purposes it is considered a priori according to some rules that may or may not apply to each building. Such ductility parameters are mostly based on the response of a single degree of freedom system to ground motions. However, it has been probed that th...

Nowadays the waste from protein fibres represents an important renewable source for a new generation of biomaterials and promising competitors for carbohydrate based biomaterials. Regenerated keratin biomaterials are biodegradable in vivo and in vitro, biocompatible, and support cell attachment and proliferation; however, their major drawback has been their weak mechanical properties such as du...

high performance fiber reinforced cementitious composite (hpfrcc) materials exhibit strain hardening behavior with multiple cracking under tensile loading. in this paper, experimental and parametric studies are performed to assess the influence of using hpfrcc material instead of normal concrete in reinforced concrete beams. after calibrating the experimental results, the analytical results inc...

Flanged shear walls are used extensively in moderate- and high-rise buildings to resist lateral loads induced by earthquakes. The seismic performance of many buildings is, therefore, closely linked to the behavior of the reinforced concrete walls. They must be carefully designed to provide not only adequate strength, but also sufficient ductility to avoid brittle failure under strong lateral lo...