The recent application of nanotechnology to structural materials is a promising way to produce new strong materials that exceed current limitations. Grain-size refinement is considered as one of the most effective strengthening methods of materials. At the same time, the addition of carbon nanotubes (CNTs) in a material is known to be more effective than conventional reinforcements. Here, CNT/C...

an ultrafine grained dual phase (ufg dp) steel containing niobium was produced by a new routeutilizing simple cold-rolling and subsequent intercritical annealing of ferrite/martensite duplex startingstructures. the effects of intercritical holding time on the microstructural evolutions and mechanicalproperties were studied. the results showed that increasing intercritical holding time enhnaced ...

V.A. Andreyachshenko, Faculty of Nanotechnology and Metallurgy, Karaganda state technical University, Karaganda, Kazakhstan A.B. Naizabekov, Mining and Metallurgy Faculty, Rudny Industrial Institute, Rudny, Kazakhstan In the present research, equal channel angular pressing (ECAP) was conducted. The defectness degree of the alloy for one pass and maximum strain was determined. Ultra fine grained...

the effect of pre-existing nano sized precipitates on the mechanisms and rate of grain refinement has been investigated during the severe plastic deformation. a binary al–0.2sc alloy, containing coherent al3sc particles, of 3.62 nm in diameter has been deformed by accumulative roll bonding up to 10 cycles. the resulting deformed structures were quantitatively analyzed using electron backscatter...

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...

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...

Aluminum alloys with nanocrystalline (NC) and ultrafine grain (UFG) size are of interest because of their strengths that are typically 30 pct greater than conventionally processed alloys of the same composition. In this study, UFG AA 5083 plate was prepared by quasi-isostatic (QI) forging of cryomilled powder, and the microstructure and mechanical behavior was investigated and compared with the...