Saeed Hasani | Yazd University (original) (raw)

Papers by Saeed Hasani

Materials Science And Engineering: B, Nov 1, 2023

Journal of Aquaculture Research and Development, 2012

Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science, May 3, 2019

In this study, the mechanism of nonisothermal oxidation of magnesium powder was determined using ... more In this study, the mechanism of nonisothermal oxidation of magnesium powder was determined using a tension analysis, which was performed by mathematical modeling and the finite element method. The results revealed that phase transformation of magnesium hydroxide to magnesium oxide in the oxide layer plays an important role in this process so that formation of magnesium hydroxide in the early stages of oxidation (< 450°C) leads to the formation of compressive stresses through the oxide layer, and as a result, the beginning of measurable oxidation is delayed. The results obtained by the mathematical model and finite element method were validated by the experimental results.

Computational Materials Science, Feb 1, 2018

Abstract The plastic-deformation behavior of the FeCo intermetallic compound with CsCl-type B2 st... more Abstract The plastic-deformation behavior of the FeCo intermetallic compound with CsCl-type B2 structure is investigated using ab initio techniques. For that purpose, stacking-fault energies (intrinsic, extrinsic, and twinning), the entire γ -surface, the shear strength, the cleavage energy, and the cleavage strength are calculated in { 1 1 ¯ 2 } and { 1 1 0 } planes of the compound single crystal. Analyzing γ -surfaces reveals the existence of stable anti-phase boundaries in both planes. Moreover, the favored slip system in this compound is found to be { 1 1 0 } [ 1 ¯ 1 1 ] . The brittle/ductile response of the material is investigated within the Rice model. It is found that both planes are equally important when investigating the brittle/ductile behavior of this compound. In agreement with observed experiments, the model successfully predicts the brittle behavior of this compound against an applied stress.

Journal of Alloys and Compounds, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Journal of Sol-Gel Science and Technology

Acta Physica Polonica A

A series of the (Fe36Co36Y8B20)100−xNbx (x = 0, 0.1, and 0.5 at.%) and (Fe36Co36Y8B20)100−xCux (x... more A series of the (Fe36Co36Y8B20)100−xNbx (x = 0, 0.1, and 0.5 at.%) and (Fe36Co36Y8B20)100−xCux (x = 0 and 0.1 at.%) amorphous alloys were fabricated by a conventional copper mold casting technique. The effects of the minor addition of niobium (Nb) and copper (Cu) on their thermal properties and glass-forming ability were discussed in detail. The results of X-ray diffraction and differential scanning calorimetry tests showed that the partial addition of Nb and Cu can effectively change the thermal properties and thermal stability of the investigated alloys. Hence, the glass-forming ability criteria, including supercooled liquid region (∆Tx), reduced glass transition temperature (Trg), criterion α, and criterion β, were calculated to evaluate the thermal stability. The supercooled liquid region was increased from 120 • C for Nb-free alloy to 138 and 127 • C for the alloy with 0.5 at.% Nb and 0.1 at.% Cu, respectively. As a result, the high glass-forming ability of the FeCo-based glass alloys and the improvement of this property by adding Nb and Cu may encourage the use of these alloys in future industrial devices. topics: bulk metallic glass (BMG), glass-forming ability, thermal stability, differential scanning calorimetry

Journal of the Australian Ceramic Society

Journal of Thermal Analysis and Calorimetry

Acta Physica Polonica A, 2020

In the present study, the effect of cooling rate on the glass forming ability of Fe41Co7Cr15Mo14Y... more In the present study, the effect of cooling rate on the glass forming ability of Fe41Co7Cr15Mo14Y2C15B6 bulk metallic glass was investigated. For this purpose, three samples with a mentioned nominal composition were prepared with diameters of 2 mm in water-cooled copper, and 2.5 mm and 3 mm in graphite molds. The amorphicity of the samples were confirmed by X-ray diffraction (XRD). Also, thermal behavior of the glassy samples was evaluated with a differential scanning calorimeter (DSC) from ambient to 1200 • C. The characteristics temperatures, such as the glass transition temperature (Tg), the onset temperature of crystallization (Tx), solidus (Tm), and liquidus (T l) temperatures were determined by using DSC curves. The results calculated by using the various criteria (i.e., Trg = Tg/T l , ω = (Tg/Tx) − (2Tg/(T l + Tg)), δ = Tx/(T l − Tg), and New β = (Tx × Tg)/(T l − Tx) 2) revealed that the thermal stability of this BMG was increased by decreasing the cooling rate. On the other hand, Tang's isoconversional method was used to determine the activation energy of crystallization in these samples. These results confirmed that activation energy of crystallization process was increased by decreasing the cooling rate, which was in good agreement with that were calculated by various criteria. Finally, an increase in the GFA can be related to the formation of clusters in the amorphous matrix with a decrease in the cooling rate and thus change the chemical composition of the amorphous matrix. topics: bulk metallic glasses (BMGs), glass forming ability (GFA), kinetics, isoconversional method, activation energy

تحقیقات علوم چوب و کاغذ ایران, 2015

AbstractAmong the forest diseases, fungi are the most important factors that cause irreparable lo... more AbstractAmong the forest diseases, fungi are the most important factors that cause irreparable losses to the wood in standing trees and logs. Fungi are the cause of contamination and decay of trees and timbers in forest or in the stock of factories. Decayed woods are one of the biomass resources and a great amount of decayed woods in the forests are not viable. In this study some experiments were conducted in order to investigate the effect of Coriolus versicolor decay on compounds obtained from beech wood (Fagus orientalis L.) pyrolysis and preparation of various and valuable chemicals. Separation and identification of chemical compounds in sound wood and decayed wood of beech was conducted by using pyrolysis method at 500° C and in nitrogen atmosphere. Separation and identification of extracted chemical compounds was carried out using sailylation of these compounds by N, O-bis (trimethylsilyl) trifluoroacetamide and also using Gas Chromatography and Mass Spectrometry method. Total...

Acta Physica Polonica A, 2021

This paper presents the results of research on the magnetic saturation polarisation, as a functio... more This paper presents the results of research on the magnetic saturation polarisation, as a function of temperature, for rapidly-cooled iron alloys with an amorphous structure. The rapidly-cooled Fe-based amorphous alloys are characterised by good magnetic properties. The Curie temperature is one of the main parameters that determine the stability of the ferromagnetic properties of such alloys. The tested materials met the assumptions of Heisenberg's theory; therefore, the critical factor, β = 0.36, was used to determine the Curie temperature. It was found that both of the tested alloys have one Curie temperature pertaining to the amorphous matrix-which proves their effective homogenisation.

New Journal of Chemistry, 2021

Copper sulfide nanostructures with different morphologies were used as a photocatalyst and antitu... more Copper sulfide nanostructures with different morphologies were used as a photocatalyst and antitumor drug delivery.

Materials Science and Engineering: A, 2021

Abstract Various contributors have been suggested so far to explain the variation of mechanical p... more Abstract Various contributors have been suggested so far to explain the variation of mechanical properties of Fe–Co–V magnetic alloys, but a comprehensive understanding is still lacking. In the present study, the variation of hardness, tensile yield strength (YS), and elongation at room temperature were determined for an 86% cold-rolled Fe–50Co–10V (wt.%) alloy after annealing at the temperature range of 300–1050 °C for holding times from 10 to 240 min. The potential contributing factors were analyzed and discussed. Detailed microstructural evolution and magnetic properties have been reported earlier for this alloy. The results showed an increase in hardness and YS but a reduction in elongation after annealing at temperatures between 450 and 550 °C for all holding times. The activation energy of the contributing process in increasing the hardness after annealing between 300 and 550 °C was 132–144 kJ/mol, being a typical value for the ordering transition in ferrite in Fe–Co and Fe–Co–2V alloys. The YS increased up to an annealing temperature of 450 °C, followed by a decreasing trend at higher annealing temperatures even in the ordered state, obviously due to i) the recovery and recrystallization of ferrite, ii) decreasing the number of (Co,Fe)3V precipitates and iii) increasing fraction of retained austenite. The elongation decreased to nil after annealing at 450–550 °C, but it was improved even in the ordered state at 600 °C and above due to the same factors which decreased the YS. The intergranular failure mode after annealing below 600 °C converted to ductile mode at 650 °C. Considering the combination of mechanical and magnetic properties, the annealing treatment at 650 °C for 10 min can be recommended for this alloy, providing high YS, a few percent elongation, and high magnetic hardness.

Journal of Alloys and Compounds, 2019