This study addresses the fabrication of nanocrystalline Fe–Co–Ni alloy using two operations: mechanical alloying (MA) of elemental powders and hot pressing (HP). The evolution of the phase composition and structure of the powder particles after MA was investigated. Ball milling with rotation speed 700 rpm for 15–20 min allows the production of a bcc Fe-based supersaturated solid solution. Durin...

The microstructure of three different nanocrystalline materials with hexagonal crystal structure are studied by X-ray diffraction peak profile analysis. The crystallite size distribution and the dislocation structure are determined in plasmathermal silicon nitride powder, sintered tungsten carbide and severely deformed titanium and are compared with transmission electron microscopy (TEM) result...

We demonstrate the application of a low-temperature carbon counter electrode with good flexibility and high conductivity in fabricating perovskite solar cells. A modified two-step method was used for the deposition of nanocrystalline CH3NH3PbI3 under high relative humidity. The carbon counter electrode was printed on a perovskite layer directly, with different sizes of graphite powder being emp...

Nanocrystalline Zinc Oxide (ZnO) powders with different morphology have been successfully synthesized by using different surfactants such as Cetyl Trimethyl Ammonium Bromide (CTAB), Sodium Dodecyl Sulphate (SDS), and Tri Ethanol Amine (TEA) via hydrothermal method. The products were characterized by means of powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electr...

This study focuses on the extraction of nanocrystalline cellulose ( NCC) from the dried stalk of Corchorus olitorius, commonly known as jute, using a combination of a microwave-assisted alkaline peroxide pulping process (AHP) and ultrasonication. Dried jute stalk powder was pretreated using sodium hydroxide under microwave irradiation for the removal of lignin. The partially delignified sample ...

abstract : alumina (al 2 o 3 ) is one of the most practical ceramics used in making ceramic-metal armours. to improve the properties of alumina, some other materials are added to it. in this paper, sic material as nano powder is added to alumina, and four armour samples of this new ceramic with different volume fractions (v.f. ) including 0%, 5%, 10% and 15% of sic particles are made. then, the...

The influence of high energy-ball milling (HEBM) on corrosion and hardness age hardening aluminum alloys was investigated. Nanocrystalline (AA2024, AA6061 AA7075) were produced by HEBM pre-alloyed powder subsequent cold compaction under uniaxial pressure 3 GPa. Cyclic potentiodynamic polarization immersion tests conducted in 0.6 M NaCl solution which revealed significantly increased pitting pro...

In the present investigation, γ-alumina nanoparticles with particle sizes less than 10 nm, high specific surface area (351 m2/g), high pore volumes and relatively narrow pore sizes distribution was prepared via sol-gel method in presence of aluminum isopropoxide as an aluminum precursor, distilled water, acetic acid as hydrolysis rate controller and tert-butanol as solvent. They had meso ...