Morphology and Physical Studies of Nanostructured Fe64Cr36 Alloy Elaborated by Ball Milling

2013 ◽  
Vol 26 ◽  
pp. 75-81 ◽  
Author(s):  
S. Triaa ◽  
L. Faghi ◽  
F. Kali-Ali ◽  
M. Azzaz
Keyword(s):  
Milling Time ◽  
High Energy ◽  
The Body ◽  
Analysis Method ◽  
X Ray Diffraction ◽  
Bcc Structure ◽  
Iron Phase ◽  
Electron Microscopes ◽  
Xrd Patterns ◽  
Scanning Electron Microscopes

Nanostructured iron based alloy, elaborated from pure elemental powders by mechanical milling at high energy was studied. The materials obtained were characterized by several techniques, such as X-ray diffraction (XRD), which allowed the dissolution of chromium in the iron phase as a function of milling time. The peaks indicate that the obtained solid solution has the body centred cubic (bcc) structure, for a speed of 250 rpm after 24 hours milling time. The Williamson - Hall analysis method was used to exploit the recorded XRD patterns. The crystallite size of about 14 nm and the microstrain of about 0.90% were obtained for 48 hours of milling. Scanning electron microscopes (SEM) and EDX analysis have confirmed the refining of milled particles as a function of milling time and the homogenization of our powders. The measurement of reflection coefficient has revealed an increase in the microwave absorption versus milling time and has confirmed the formation of our alloy during 24 hours of milling.

Effects of Mechanical Alloying on the Structure and Properties of Iron Powders

2015 ◽  
Vol 364 ◽  
pp. 132-138
Author(s):  
F. Lemdani ◽  
Mohammed Azzaz ◽  
K. Taïbi ◽  
A. Lounis
Keyword(s):  
Magnetic Behavior ◽  
High Energy ◽  
The Body ◽  
X Ray Diffraction ◽  
Laser Scattering ◽  
Different Types ◽  
Bcc Structure ◽  
Electron Microscopes ◽  
Diffraction Patterns ◽  
Scanning Electron Microscopes

A nanostructured iron, elaborated from pure elemental powders by mechanical milling at high energy was characterized by different types of technical of analysis. Scanning electron microscopes (SEM) and laser scattering machine have showed the variation in the size and the shape of particles according to different milling times. Powders obtained were characterized with X-ray diffraction (XRD) , the latter diffraction patterns indicated the body centered cubic (bcc) structure. The crystalline grain was about 13 nm size after only a few hours of milling time. The measurement of both coercive field (Hc) and maximal magnetization (Ms) revealed a change in the magnetic behavior of our samples.

Nickel Silicides Synthesized by High Energy Ball Milling

2007 ◽  
Vol 353-358 ◽  
pp. 1625-1628 ◽  
Author(s):  
Gen Shun Ji ◽  
Qin Ma ◽  
Tie Ming Guo ◽  
Qi Zhou ◽  
Jian Gang Jia ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Milling ◽  
Milling Time ◽  
High Energy ◽  
Planetary Mill ◽  
High Energy Ball Milling ◽  
X Ray Diffraction ◽  
Microstructure Morphology ◽  
Energy Ball ◽  
Xrd Patterns

The high energy ball milling of Ni-50 atom % Si elemental powder mixtures was carried out using a planetary mill. X-ray diffraction (XRD) was used to identify the phase evolutions during the high energy ball milling period. The microstructure morphology of the powders milled different time was determined by field emission scanning electron microscope (FESEM). The beginning time of mechanical alloying was determined by back scattered electrons (BSE) images. The XRD patterns showed that the nickel peaks intensity and the silicon peaks intensity obviously decreased with milling time increased to 1 hour. BSE images revealed that nickel and silicon powders were not blended uniformly for 1 hour of milling. It was found that NiSi formed as the milling time increased to 5 hours, simultaneously, the nickel peaks and the silicon peaks almost disappeared. That means the obvious mechanical alloying started from 5 hours of milling. BSE images agreed with the result analyzed from XRD patterns. With the milling time further increased from 10 to 75 hours, the NiSi peaks decreased gradually, at the same time, the Ni2Si peaks appeared and then increased gradually.

THE EFFECT OF Mn ON α TO γ TRANSFORMATION IN THE NANOSTRUCTURED HIGH NITROGEN Fe-Cr-Mn STAINLESS STEEL PRODUCED BY MECHANICAL ALLOYING

2012 ◽  
Vol 05 ◽  
pp. 49-57
Author(s):  
FARIBA TEHRANI ◽  
MOHAMMAD HASAN ABBASI ◽  
MOHAMMAD ALI GOLOZAR ◽  
MASOUD PANJEPOUR
Keyword(s):  
Grain Size ◽  
Stainless Steel ◽  
Mechanical Alloying ◽  
Milling Time ◽  
High Energy ◽  
Nitrogen Atmosphere ◽  
Transformation Rate ◽  
X Ray Diffraction ◽  
High Nitrogen ◽  
Xrd Patterns

In this study, the effect of Mn on α to γ transformation in the nanostructured high nitrogen Fe -18 Cr - xMn stainless steel produced by mechanical alloying (MA) was investigated. MA was performed under nitrogen atmosphere using a high-energy planetary ball mill. X- ray diffraction (XRD) patterns of produced samples showed that α to γ transformation starts after 20 hours of milling and propagates by increasing the milling time. Completion of this phase transformation occurred in the Fe -18 Cr -8 Mn sample after 100 hours of milling. But, in the Fe -18 Cr -7 Mn sample, some α phase remained even after 150 hours of milling. Also, nitrogen analysis revealed that nitrogen solubility in the milled powders increased significantly by increasing the milling time, and ultimately reached 1wt%. This is believed to be due to the increase of the lattice defects and development of nanostructure through MA. Variations in grain size and internal lattice strain versus milling time in both cases showed that the critical ferrite grain size for austenite nucleation was lower than 10nm. Moreover, a lower transformation rate was found in samples containing lower Mn content.

Analysis on Microstructure of Laser Brazing Diamond Grits with a Ni-Based Filler Alloy

2010 ◽  
Vol 97-101 ◽  
pp. 3879-3883 ◽  
Author(s):  
Zhi Bo Yang ◽  
Jiu Hua Xu ◽  
Ai Ju Liu
Keyword(s):  
Active Element ◽  
Steel Substrate ◽  
Parameters Optimization ◽  
Interfacial Region ◽  
Filler Alloy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cross Diffusion ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes

Brazing diamond grits onto steel substrate using a Ni-based filler alloy was carried out via laser beam in an argon atmosphere. The microstructure of the interfacial region among the Diamond grits and the filler layer were investigated by means of scanning electron microscopes (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). Meanwhile, the formation mechanism of carbide layers was discussed. All the results indicated that the active element chromium in the Ni-based alloy concentrated preferentially to the surface of the grits to form a chromium-rich layer, and the hard joint between the alloy and the steel substrate is established through a cross-diffusion of iron and Ni-based alloy through parameters optimization.

Microstructure Evolution of a Fine Grain Al-50wt%Si Alloy Fabricated by High Energy Milling

2011 ◽  
Vol 479 ◽  
pp. 54-61 ◽  
Author(s):  
Fei Wang ◽  
Ya Ping Wang
Keyword(s):  
Grain Growth ◽  
Microstructure Evolution ◽  
Room Temperature ◽  
Milling Time ◽  
High Energy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Laser Method ◽  
X Ray ◽  
Fine Grain

Microstructure evolution of high energy milled Al-50wt%Si alloy during heat treatment at different temperature was studied. Scanning electron microscope (SEM) and X-ray diffraction (XRD) results show that the size of the alloy powders decreased with increasing milling time. The observable coarsening of Si particles was not seen below 730°C in the high energy milled alloy, whereas, for the alloy prepared by mixed Al and Si powders, the grain growth occurred at 660°C. The activation energy for the grain growth of Si particles in the high energy milled alloy was determined as about 244 kJ/mol by the differential scanning calorimetry (DSC) data analysis. The size of Si particles in the hot pressed Al-50wt%Si alloy prepared by high energy milled powders was 5-30 m at 700°C, which was significantly reduced compared to that of the original Si powders. Thermal diffusivity of the hot pressed Al-50wt%Si alloy was 55 mm2/s at room temperature which was obtained by laser method.

scholarly journals Controllable Hydrothermal Synthesis and Photocatalytic Performance of Bi2MoO6 Nano/Microstructures

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1161
Author(s):  
Tao Ji ◽  
Enna Ha ◽  
Mingzhou Wu ◽  
Xin Hu ◽  
Jie Wang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Ammonium Bromide ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Facile Hydrothermal Route ◽  
Nanoparticle Aggregates ◽  
Electron Microscopes ◽  
Cetyl Trimethyl Ammonium ◽  
Scanning Electron Microscopes

Bi2MoO6 with a tunable morphology was synthesized by a facile hydrothermal route using different surfactants, including nanosheet-assembled microspheres, smooth microspheres, nanoparticle aggregates and nanoparticles. The morphology, crystal structure and photocatalytic activity of as-obtained Bi2MoO6 were characterized by scanning electron microscopes (SEM), X-ray diffraction (XRD), photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) and UV–Vis spectrophotometer. Bi2MoO6 flower-like microspheres using cetyl-trimethyl-ammonium bromide (BET) as the surfactant exhibited much better photocatalytic activity than Bi2MoO6 with the other morphologies, with a degradation efficiency of 98.4%. It can be summarized that the photocatalytic activity of Bi2MoO6 samples depends on their morphology and composition.

Appropriate Conditions for Preparation of Nanosized WO3 through High-Energy-Milling

2011 ◽  
Vol 194-196 ◽  
pp. 665-668
Author(s):  
Chun Huan Chen ◽  
Rui Ming Ren
Keyword(s):  
Grain Size ◽  
Milling Time ◽  
Rotation Speed ◽  
Processing Parameters ◽  
High Energy ◽  
Charge Ratio ◽  
Activation Process ◽  
X Ray Diffraction ◽  
High Energy Milling ◽  
Transmission Electron

In order to synthesize WC-Co nanopowders through an integrated mechanical and thermal activation process, WO3-Co2O3-C nanopowders need to be obtained first. It is critical how to obtain the WO3-Co2O3-C nanopowders efficiently. The effect of processing parameters on the grain size during high-energy-milling of WO3-Co2O3-C mixed powders was studied via X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the grain size of reactants can be effectively decreased with increasing the milling time, rotation speed, and charge ratio. After a certain time milling, both WO3 and C powders achieve nano-level in grain size and mixed homogeneously. The appropriate milling parameters for fabricating nanosized WO3+C+Co2O3 powders are suggested to be 4 to 8 hours of milling time, 400 RPM of rotation speed, and 40:1 to 60:1 of charge ratio.

Investigations on the Structural, Optical and Dielectric Properties of Ball-Milled ZnO–Fe2O3 Nanocomposites

2020 ◽  
Vol 19 (04) ◽  
pp. 1950034
Author(s):  
V. Balachandar ◽  
J. Brijitta ◽  
K. Viswanathan ◽  
R. Sampathkumar
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Ball Milling ◽  
High Energy ◽  
X Ray Diffraction ◽  
Dielectric Constant And Loss ◽  
Energy Ball ◽  
Uv Visible ◽  
Ball Milling Technique ◽  
Xrd Patterns

In this study, ZnO–Fe2O3 nanocomposites were prepared by high-energy ball milling technique and characterized through X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), UV–visible spectroscopy and dielectric spectroscopy. The amount of Fe2O3 in the ZnO–Fe2O3 nanocomposites was varied at the rates of 1[Formula: see text]wt.%, 3[Formula: see text]wt.% and 5[Formula: see text]wt.% in order to investigate its influence on the structural, optical and dielectric properties of the nanocomposites. XRD patterns of nanocomposites revealed no shift in peak positions and hence confirmed the formation of composites after ball milling. Further, it was observed from FESEM analysis that Fe2O3 particles were distributed randomly on the ZnO matrix of the nanocomposites. ZnO–Fe2O3 nanocomposites reveal extended optical absorption in the range of 400–600[Formula: see text]nm from UV studies. The dielectric constant and loss of the nanocomposites decrease exponentially with increase in frequency. The composition and frequency dependences of the dielectric constant, dielectric loss and AC conductivity are explained based on the Maxwell–Wagner effect and Koop’s theory.

Otosclerotic Stapes: Morphological and Microchemical Correlates

1977 ◽  
Vol 86 (4) ◽  
pp. 525-540 ◽  
Author(s):  
David J. Lim ◽  
William H. Saunders
Keyword(s):  
Calcium Salt ◽  
Mineral Deposit ◽  
Ground Substance ◽  
X Ray Diffraction ◽  
Typical Pattern ◽  
X Ray ◽  
Initial Stage ◽  
Electron Microscopes ◽  
Sclerotic Lesions ◽  
Scanning Electron Microscopes

A total of 32 otosclerotic stapes is thin-sectioned without decalcification and examined using transmission and scanning electron microscopes, with a nondispersive x-ray analyzer attached to the latter. These otosclerotic stapes are classified as spongiotic, sclerotic, or preotosclerotic, according to their pathologic characteristics and state of mineralization. Either diffuse or patchy demineralization in the ground substance appears to be the initial stage of otosclerosis, and this area coincides with preotosclerotic lesions (also known as blue mantle) in light microscopy. Therefore, it is interpreted that demineralization precedes the destruction of ground substance in the preotosclerotic lesion. Bone mineral deposits in new otosclerotic bone appear to be related to the collagen fibrils that are embedded in the ground substance. No mineral deposit could be seen without the ground substance deposition; therefore, it is suggested that this ground substance is the single most important factor in the poor mineralization of the otosclerosis. The sclerotic lesions are well mineralized and show a typical pattern of hydroxyapatite by x-ray diffraction study. We could not confirm the notion that the sclerotic lesion is hypermineralized as compared to the normal stapes. The spongiotic lesions are poorly mineralized, with low calcium salt. Using the Ca/P ratio and x-ray diffraction pattern as criteria, it was determined that spongiotic lesions belong to unstable, immature bone.

High-energy synchrotron X-ray diffraction measurements of simple bending of pseudoelastic NiTi shape memory alloy wires

2016 ◽  
Vol 31 (2) ◽  
pp. 104-109 ◽  
Author(s):  
Baozhuo Zhang ◽  
Marcus L. Young
Keyword(s):  
Phase Transformation ◽  
Shape Memory ◽  
High Energy ◽  
Bend Angle ◽  
Niti Shape Memory Alloy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Mechanical Bending ◽  
Xrd Patterns

Many technological applications of austenitic shape memory alloys (SMAs) involve cyclical mechanical loading and unloading in order to take advantage of pseudoelasticity. In this paper, we investigated the effect of mechanical bending of pseudoelastic NiTi SMA wires using high-energy synchrotron radiation X-ray diffraction (SR-XRD). Differential scanning calorimetry was performed to identify the phase transformation temperatures. Scanning electron microscopy images show that micro-cracks in compressive regions of the wire propagate with increasing bend angle, while tensile regions tend not to exhibit crack propagation. SR-XRD patterns were analyzed to study the phase transformation and investigate micromechanical properties. By observing the various diffraction peaks such as the austenite (200) and the martensite (${\bar 1}12$), (${\bar 1}03$), (${\bar 1}11$), and (101) planes, intensities and residual strain values exhibit strong anisotropy, depending upon whether the sample is in compression or tension during bending.

Sign in / Sign up

Export Citation Format

Share Document