The study of nucleation mechanism of new grains during severe plastic deformation of magnesium alloys is of great importance to control the characteristics of final microstructures.  To investigate the role of discontinuous recrystallization, a wrought AZ31 magnesium alloy was deformed by accumulative back extrusion process at 330 °C.  The obtained microstructures were studied using optical and...

AISI 304L austenitic stainless steel with different grain sizes of 0.5 -12 μm was obtained through the martensitic process. Corrosion behavior of different samples was investigated in a 0.5M HCl solution using open circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy tests. Also, the correlation between the grain size and pitting corrosion resistance was as...

ZrO2 nanograins annealed at different temperatures are systematically investigated using x-ray diffraction ~XRD! and Raman spectroscopy. Our results show that bulk properties of nano-ZrO2 diminish but the defect-, surface-, and size-related features display as grain size decreases. A critical size that divides respective predominance is determined to be about 15 nm. Both XRD and Raman spectra o...

In this study, the effects cold rolling and annealing parameters during thermomechanical processing of the AISI 201LN stainless steel were investigated. The cast samples were homogenized, hot-rolled and solution-annealed to acquire a suitable microstructure for the subsequent thermomechanical treatment. Unidirectional and transverse multi-pass cold rolling at 25, 0 and -15 °C was carried out to...

In the present work, nano/ultrafine structured Al/Brass composite was produced by accumulative roll bonding (ARB) up to eight cycles. The evolution of grain refinement and deformation texture and their effect on the mechanical properties were investigated. It was observed that by increasing the ARB cycles, due to the difference in flow properties of the metal constituents, brass layers necked, ...

Silver (Ag) is one of the seven metals of antiquity and an important engineering material in the electronic, medical, and chemical industries because of its unique noble and catalytic properties. Ag thin films are extensively used in modern electronics primarily because of their oxidation-resistance. Here we report a novel phenomenon of Ag nano-volcanic eruption that is caused by interactions b...

The unique concept of phase reversion involving severe deformation parent austenite into martensite, followed by annealing for a short duration, whereby the strain-induced martensite reverts to austenite, was adopted obtain nano-grained/ultrafine-grained (NG/UFG) structure in Cu-bearing biomedical austenitic stainless steel resulting high strength-high ductility combination. Work hardening and ...

Large super-elasticity approaching its theoretically expected value was achieved in Ti-13.3Nb-4.6Mo alloy having an ultrafine-grained ?-phase. In-situ synchrotron radiation X-ray diffraction analysis revealed that the dominant yielding mechanism changed from dislocation slip to martensitic transformation by decreasing ?-grain size down sub-micrometer. Different grain dependence of critical stre...

Abstract There are various methods to produce iron based nano crystalline magnetic alloys. Among these methods, mechanical alloying is one of the most important. In this research, nano crystalline Fe85Si10Ni5 soft magnetic alloy was synthesized by mechanical alloying. The effect of alloying time on phase constituents and magnetic properties of the produced powders was investigated, by X-ray di...