Nanostructured (NS) and ultrafine-grained (UFG) materials have high strength and relatively low ductility. Their toughness has not been comprehensively investigated. Here we report the Charpy impact behavior and the corresponding microstructural evolutions in UFG Cu with equi-axed and elongated grains which were prepared by equal channel angular pressing (ECAP) for 2 and 16 passes at room tempe...

BACKGROUND Cochlear implants stimulate the auditory nerve to enable hearing. Determining appropriate upper and lower limits of stimulation is essential for successful cochlear implantation. The intraoperative evoked stapedius reflex threshold (ESRT) and evoked compound action potential (ECAP) are commonly used to determine the limits of implant stimulation. In this study, we evaluated the dose-...

Introduction: Electrically evoked compound action potential (ECAP) is an objective auditory response that can be used in the programing of cochlear implants. The aims of this study were to monitor ECAP thresholds and auditory, language and speech progress for 6 months after cochlear implant surgery and to evaluate any relationship between them.   Materials and Methods: Ten children with a m...

An AZ31 magnesium alloy was extruded and then processed by equal-channel angular pressing (ECAP) at 200 °C for 1, 2 4 passes. The grain structure refined from 20.2 to 1.6 ?m after shear punch testing (SPT) technique uniaxial tensile tests were employed evaluate the mechanical properties of ECAP samples. pass showed lower yield stress higher ductility compared as-extruded condition, indicating t...

Equal channel angular Pressing (ECAP) is an innovative technique for developing ultrafine-grained microstructures first developed by Segal et al in 1981 in the former Soviet Union. The ECAP method consists of two channels that intersect at an angle, generally comprised between 90◦ and 135◦ . The deformation is produced by shear as the billet is extruded through the channels. One of the geometri...

Abstract This study investigated the impact of equal channel angular pressing (ECAP) combined with heat treatments on microstructure and mechanical properties AlSi10Mg alloys fabricated via selective laser melting (SLM) gravity casting. Special attention was directed towards determining effect post-fabrication microstructural evolution alloy using two different routes. Three initial conditions ...

Mechanism of fatigue crack initiation was investigated in ultrafine-grained (UFG) magnesium alloy AZ91 processed by equal channel angular pressing (ECAP). Fatigue behaviour of UFG material was compared to the behaviour of material in an initial as-cast state. Focused ion beam technique (FIB) was applied to reveal the surface relief and early fatigue cracks. Two substantially different mechanism...

among different spd techniques, equal channel angular pressing has attracted the most attentions,because of applying large strain to solid bulk materials. in this research, ecap process up to 6passes was carried out on a pure copper and a 6012 al-mg-si alloy with bc route in ecap dieswith φ=120 and ψ=20 and diameter of 20and 10 millimeter respectively. moreover, x-raydiffraction (xrd) system wa...