Showing 4 results for Ghorbani
N.najaf- Zadeh, M.ghorbani,
Volume 15, Issue 1 (7-1994)
Abstract
The effects of carbon content on the dynamic and static softening mechanisms of Ti microalloy steels were investigated both in ferrite and austenite regions.
The results obtained showed that recrystallization rate decreased as the percentage of carbon content was increased from 0.0035 to 0.110. This is due to the Ti(CN) and TiC precipitates and also the free carbon content. In the ferrite region, the main obstacles for dynamic recrystallization are interstitial elements such as C and N. The interrupted compression tests also showed that increasing temperature leads to the increasing rate of static recovery and recrystallization in both ferrite and austenite regions.
M. Ghorbani and A.m. Saedi,
Volume 24, Issue 2 (1-2006)
Abstract
Nanowire is a cylindrical nano-structure with nanometer dimensions. In this research, the studied nanowire was made from the magnetic triple Ni-Fe-Co alloy.
We utilized ordered porous anodic aluminum oxide as a template for the nanowire deposition. The nanowire arrays were electrodeposited in the cylindrical pores of the oxide layer by AC potential in a simple sulfate bath. Then the relation of shape and composition of the nanowires with their fabrication parameters was investigated. The results showed that the barrier layer modification had an essential role in the deposition process and a composition gradient was detected in a single nanowire.
S. Shirinparvar, R.s. Razavi, F. Davar, M.r. Loghman-Estarki, S. Ghorbani,
Volume 35, Issue 4 (Journal of Advanced Materials-Winter 2017)
Abstract
In this research, the nanopowders of lanthanum and neodymium co-doped yttria were synthesized by sol-gel combustion method. Citric acid and glycine were used as the gel maker and fuel respectively. The effect of molar ratio of citric acid to glycine on the grain size and morphology was evaluated. The optimized products were characterized by X-ray diffraction (XRD), field-emission scanning electron microscope (FESEM), transmission electron microscope (TEM), UV–visible (UV–Vis), thermal gravimetric-differential thermal analysis (TG/DTA), and Fourier transform infrared spectrometer (FTIR). The optimized products which are synthesized with a molar ratio citric acid to glycine 1.06:1.06 have an average grain size of 30-40nm with spherical morphology, and without agglomeration. Also, their band gap is 3.29eV.
M. Ghorbani, H. Khorsand,
Volume 40, Issue 2 (Journal of Advanced Materials-Summer 2021)
Abstract
Strontium hexaferrite M-type nanoparticles doped with La and Cu (SrFe12-xCuxO19-Sr1-xLaxFe12-xCuxO19) with different mole fractions (x=0.1-0.2-0.3-0.4-0.5) synthesized by self-combustion sol-gel technique. Firstly, a gel of metal nitrates with the above-mentioned mole fractions were fabricated and the obtained powder was cured at 950°C. Microstructural properties and the morphology of the compounds were investigated by employing X-ray diffraction (XRD) and scanning electron microscopy (SEM). Also, in order to investigate the magnetic properties, Vibrating Sample Magnetometer (VSM) was used. SEM images revealed that the particles had an average size of about 100 nm. Cu2+ ions were substituted with Fe3+ ions within the crystalline sites of SrFe12O19 structure. It was shown that the lattice parameter (a) remained approximately unchanged with an increase in Cu-dopped while the lattice parameter (c) decreased with increasing the mole fraction (x). By using VSM hysteresis diagrams, it was observed that the saturated magnetization and coercive force increased with the addition of La; this was attributed to the variation in the distribution of ions and the shape anisotropy of the nanoparticles. These significant changes in the magnetic properties were for the sample with the composition of Sr1-xLaxFe12-xCuxO19 and SrFe12-xCuxO19, for the x=0.1 and x=0.5, respectively.
