scholarly journals Study of The Influence of Chromium on A Cobalt Iron Alloy

2020 ◽  
Author(s):  
smain mebrek ◽  
mourad zergoug ◽  
nacereddine haine
Keyword(s):  
Eddy Currents ◽  
Iron Alloy ◽  
High Energy ◽  
Second Step ◽  
X Ray Diffraction ◽  
Mechanical Grinding ◽  
Cobalt Iron ◽  
Micro Deformation ◽  
Grinding Time ◽  
Electrical Study

Abstract The present work comes within the framework of research of new materials, with improved properties, which could be an important key for innovative applications. For this purpose, two types of alloys, a binary (Fe, Co) and a ternary (Fe, Co, Cr), were first synthesized by mechanical grinding at high energy, varying the grinding time. In a second step, all the samples were subjected to various characterizations, a structural study (X-ray diffraction), a morphological study (scanning electron microscopy "SEM"), a magnetic characterization (the "VSM" vibrating sample magnetometer And finally, an electrical study (eddy currents). Numerous and valuable information was then deduced to know the variations in the average lens size, the internal micro deformation, the cell parameter, the saturation magnetization, the remnant field, the coercive field as well as the Z impedance, according to a only parameter, the grinding time.

scholarly journals The Magnetic and Structural Properties of the Alloys of Iron Produced by Mechanical Alloying

2020 ◽  
Vol 5 (1) ◽  
Keyword(s):  
High Energy ◽  
Second Step ◽  
X Ray Diffraction ◽  
Mechanical Grinding ◽  
Soft Magnetic ◽  
Magnetic Systems ◽  
Maximum Value ◽  
Magnetically Hard ◽  
Average Size ◽  
Complete Formation

In this study, nanostructured powders, (Fe65Co35) 100-x Crx with (x=0, 10), were synthesized by a high-energy mechanical grinding process, usually used to obtain soft magnetic systems. For this purpose, the metal elements Fe, Co and Cr, of respective purities 99.9, 99.8 and 99.5% and of average size less than one hundred microns, were milled at different times, ranging from 1 hour to 36 hours. In a second step, the nanopowders obtained were characterized by several techniques, namely X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM) techniques. The analysis of the results obtained showed the complete formation of the (Fe65Co35) and (Fe65Co35) 90Cr10 phases from 12 hours of grinding. For (Fe65Co35), the remnant field Br and the saturation magnetization Ms have similar evolutions namely, a decrease between 8h and 24h, followed by an increase until the end of the grinding. In addition, the high values of Br and Hc suggest that this system is magnetically hard. The presence of chrome in the ternary (Fe65Co35) 90Cr10 amplifies the maximum value of Hc, while maintaining a similar behavior.

Analysis of Ground Dolomite: Effect of Grinding Time on the Production of Submicron Particles

2014 ◽  
Vol 679 ◽  
pp. 145-148 ◽  
Author(s):  
N.A. Nik Nur Azza ◽  
Hui Lin Ong ◽  
Hidayu Jamil Noorina ◽  
Hazizan Md Akil ◽  
S.T. Sam
Keyword(s):  
High Energy ◽  
Submicron Particles ◽  
X Ray Diffraction ◽  
Particle Size Reduction ◽  
Structural Pattern ◽  
Dolomite Sample ◽  
The Impact ◽  
Sem Morphology ◽  
Harmful Effects ◽  
Grinding Time

This paper discusses the effect of grinding time on the production of submicron dolomite by using the impact and abrasion technique of high energy planetary ball mill. It is known that grinding process leads to surface activation other than exhibiting particle size reduction. Most of the energy applied during the process will be dissipated as heat that could lead to harmful effects to the structural pattern of the ground material. Thus in order to study the detrimental effects of grinding towards submicron dolomite, sample was ground at 400 rpm speed with various grinding time; 0.5h, 1h, 2h, 5h, 10h and 20h. It was confirmed using X-Ray Diffraction (XRD) method that the crystalline structure of dolomite did not deform even after 20h of grinding time, thus maintained its crystallinity. The morphological structures of ungrind and ground raw dolomite were shown by Scanning Electron Microscope (SEM) morphology.

scholarly journals MWCNT-Reinforced AA7075 Composites: Effect of Reinforcement Percentage on Mechanical Properties

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 969
Author(s):  
Iria Feijoo ◽  
Gloria Pena ◽  
Marta Cabeza ◽  
M. Julia Cristóbal ◽  
Pilar Rey
Keyword(s):  
Multiwall Carbon Nanotubes ◽  
Tensile Tests ◽  
High Energy ◽  
Milling Process ◽  
Matrix Composites ◽  
X Ray Diffraction ◽  
Strip Shape ◽  
The Matrix ◽  
Micro Deformation ◽  
Scherrer Formula

Metal–matrix composites (MMC) of aluminium alloy 7075 (AA7075) containing 1 wt.% and 0.5 wt.% multiwall carbon nanotubes (MWCNTs) were developed by powder metallurgy, using a high energy ball milling (HEBM) process for dispersion of the MWCNTs. The powder of the AA7075-MWCNT obtained was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The microstructural changes produced during the milling process, such as the modification of the crystallite size, as well as the micro-deformation of the matrix crystal lattice, were determined using the Scherrer formula. After consolidation into a strip shape using the hot powder extrusion (HPE) process at 500 °C, no porosity was detected and a fine homogeneous dispersion of the reinforcement into the matrix was obtained. After performing a 0.2 HV test and tensile tests in the extruded profiles of both composites, a better combination of properties was found in samples of AA7075-0.5 wt.% MWCNT, with the increase in measured ductility being especially remarkable.

Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

2020 ◽  
Vol 38 (4A) ◽  
pp. 491-500
Author(s):  
Abeer F. Al-Attar ◽  
Saad B. H. Farid ◽  
Fadhil A. Hashim
Keyword(s):  
Ionic Conductivity ◽  
Electrochemical Impedance ◽  
Structural Information ◽  
Impedance Analysis ◽  
High Energy ◽  
Yttria Stabilized Zirconia ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Powder Morphology ◽  
X Ray

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

AMPCOLOY 570

Alloy Digest ◽  
1980 ◽  
Vol 29 (3) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Cast Iron ◽  
Iron Alloy ◽  
Heat Treating ◽  
Nickel Aluminum ◽  
High Quality ◽  
Glass Making ◽  
Temperature Performance ◽  
Wide Range ◽  
Cobalt Iron

Abstract AMPCOLOY 570 is a cast copper-nickel-aluminum-cobalt-iron alloy specially developed for applications involving severe stresses and high temperatures, such as glass-making molds and plate-glass rolls. It is significantly superior to cast iron which has been commonly used for glass-making molds. Good foundry techniques will yield high-quality castings of Ampcoloy 570 in a wide range of section sizes. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Cu-392. Producer or source: Ampco Metal Inc..

Studies about Electrochemical Plating with Zinc - nickel Alloys - the Influence of Deposition Potential on Stoichiometric Composition

2008 ◽  
Vol 59 (9) ◽  
Author(s):  
Violeta Vasilache ◽  
Gheorghe Gutt ◽  
Traian Vasilache
Keyword(s):  
Nickel Alloys ◽  
Stoichiometric Composition ◽  
Nickel Chloride ◽  
Deposition Potential ◽  
X Ray Diffraction ◽  
Pure Zinc ◽  
X Ray ◽  
Nickel Cobalt ◽  
Cobalt Iron ◽  
Electrochemical Plating

The electrochemical deposition of zinc and combinations with elements of the 8th group of the Periodic System (nickel, cobalt, iron) have good properties for anticorrosive protection, compared with pure zinc. For steel pieces, these films delay apparition and formation of white and red iron oxide. We used solutions with different concentrations of zinc chloride, nickel chloride and potassium chloride. To analyze the results we used the optic microscope and the X-ray diffraction.

scholarly journals Effects of Recycled Fe2O3 Nanofiller on the Structural, Thermal, Mechanical, Dielectric, and Magnetic Properties of PTFE Matrix

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2332
Author(s):  
Ahmad Mamoun Khamis ◽  
Zulkifly Abbas ◽  
Raba’ah Syahidah Azis ◽  
Ebenezer Ekow Mensah ◽  
Ibrahim Abubakar Alhaji
Keyword(s):  
Electron Microscopy ◽  
High Energy ◽  
Filler Loading ◽  
Complex Permeability ◽  
X Ray Diffraction ◽  
Thermal Expansion Coefficients ◽  
Transmission Electron ◽  
Energy Ball ◽  
Hematite Fe2o3 ◽  
Ptfe Composites

The purpose of this study was to improve the dielectric, magnetic, and thermal properties of polytetrafluoroethylene (PTFE) composites using recycled Fe2O3 (rFe2O3) nanofiller. Hematite (Fe2O3) was recycled from mill scale waste and the particle size was reduced to 11.3 nm after 6 h of high-energy ball milling. Different compositions (5–25 wt %) of rFe2O3 nanoparticles were incorporated as a filler in the PTFE matrix through a hydraulic pressing and sintering method in order to fabricate rFe2O3–PTFE nanocomposites. The microstructure properties of rFe2O3 nanoparticles and the nanocomposites were characterized through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM). The thermal expansion coefficients (CTEs) of the PTFE matrix and nanocomposites were determined using a dilatometer apparatus. The complex permittivity and permeability were measured using rectangular waveguide connected to vector network analyzer (VNA) in the frequency range 8.2–12.4 GHz. The CTE of PTFE matrix decreased from 65.28×10−6/°C to 39.84×10−6/°C when the filler loading increased to 25 wt %. The real (ε′) and imaginary (ε″) parts of permittivity increased with the rFe2O3 loading and reached maximum values of 3.1 and 0.23 at 8 GHz when the filler loading was increased from 5 to 25 wt %. A maximum complex permeability of 1.1−j0.07 was also achieved by 25 wt % nanocomposite at 10 GHz.

Sign in / Sign up

Export Citation Format

Share Document