The Effect of Deposition Parameters on Tensile Properties of Pulse-Plated Nanocrystalline Nickel

2000 ◽  
Vol 634 ◽  
Author(s):  
K. L. Morgan ◽  
Z. Ahmed ◽  
F. Ebrahimi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Tensile Properties ◽  
Nanocrystalline Nickel ◽  
Cathodic Current ◽  
Deposition Parameters ◽  
Current Densities ◽  
D 12 ◽  
Scanning Electron

ABSTRACTThe microstructure and tensile properties were investigated for pulse-plated nanocrystalline nickel electrodeposits prepared from an additive-free sulfamate-based solution. Square-wave cathodic current densities were varied from 25 to 75 mA/cm2. The samples deposited at 25 mA/cm2 showed the smallest grain size (d ∼ 12 nm), and the grain size was found to increase with increasing current densities. The grain size of the electrodeposits ranged from approximately 27 to 12 nm. Tensile results indicated that the yield strength of the specimens increased with decreasing grain size. Scanning electron microscopy revealed that all electrodeposits fractured through a ductile mechanism.

The Synthesis of Cu0.81Ni0.19 Intermetallics by Mechanical Alloying

2012 ◽  
Vol 496 ◽  
pp. 379-382
Author(s):  
Rui Song Yang ◽  
Ming Tian Li ◽  
Chun Hai Liu ◽  
Xue Jun Cui ◽  
Yong Zhong Jin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Elemental Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scherrer Equation ◽  
Scanning Electron

The Cu0.81Ni0.19 has been synthesized directly from elemental powder of nickel and copper by mechanical alloying. The alloyed Cu0.81Ni0.19 alloy powders are prepared by milling of 8h. The grain size calculated by Scherrer equation of the NiCu alloy decreased with the increasing of milling time. The end-product was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM)

Light Burning Condition of Preparing Dolomite Clinker Using Natural Dolomite

2018 ◽  
Vol 281 ◽  
pp. 156-162
Author(s):  
Wang Nian Zhang ◽  
Xi Tang Wang ◽  
Zhou Fu Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Burning Temperature ◽  
X Ray ◽  
Temperature Range ◽  
Scanning Electron

The influence of the light burning temperature on the sintering property of nature dolomite has been investigated by two-step sintering process in the temperature range 1500 °C to 1600 °C. The resulting bulk densities and apparent porosities of the sintered dolomite samples were examined, and analyzing the sintered dolomite by scanning electron microscopy and X-ray diffraction were performed. The results showed light burned at 850 °C for 3 h, the main phases of the dolomite with 3-5 grain size were MgO, CaO and little CaCO3, and then fired at 1600 °C,the density of sintering dolomite reached to 3.38 g/cm3, the apparent property was 1.2 %, the size of MgO grain up to 3.75 μm . However when dolomite light burned at 1050 °C for 3 h, the main phases were MgO and CaO, and then fired at 1600 °C,the density of sintering dolomite only was 3.30 g/cm3, the apparent property was 2.3 %, the size of MgO only was 3.05 μm .

The Effects of Al-Ca Compounds on Grain Refinement of Mg-Ca Alloys

2011 ◽  
Vol 686 ◽  
pp. 348-354 ◽  
Author(s):  
Shu Tao Xiong ◽  
Fu Sheng Pan ◽  
Bin Jiang ◽  
Xiao Ke Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Grain Refinement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metallic Compound ◽  
Scanning Electron ◽  
Main Factor

In the present work, Al-Ca metallic compound was prepared in Mg-Ca alloys and the effects of Al-Ca metallic compound and different Al/Ca values on the grain refinement of Mg-Ca alloys were investigated by scanning electron microscopy and X-ray diffraction, and the mechanism of grain refinement of Mg-Ca alloys was discussed. The results showed that the grain size of Mg-0.5Ca alloy was obviously reduced from 550μm to 230μm due to the addition of Al. Al2Ca phase existed in these alloys and its morphology evolved from granular to rod-like. It is regarded as the main factor for the grain refinement.

In Situ Scanning Electron Microscopy Observation of the Pattern Formation on the Surface of Al/Ge Bilayer Films

2007 ◽  
Vol 539-543 ◽  
pp. 3568-3573
Author(s):  
H. Kumagai ◽  
M. Shibata ◽  
Tomokazu Moritani ◽  
Takao Kozakai ◽  
Minoru Doi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Free Surface ◽  
Electron Microscope ◽  
Microscopy Observation ◽  
Bilayer Films ◽  
Fractal Patterns ◽  
Scanning Electron

When the Al/Ge/SiO2 bilayer films are annealed in-situ in a scanning electron microscope (SEM) at the temperatures lower than the crystallization temperature of amorphous Ge itself, the so-called metal-mediated-crystallization (MMC) takes place. In the course of MMC, crystalline Ge aggregates (Ge clusters) form in the bilayer films, which results in the formation and the evolution of impressive fractal patterns with branching on the free surface. In-situ SEM observations of annealed Al/Ge/SiO2 bilayer films indicate that the grain size of polycrystalline Al-layer influences the nucleation of Ge clusters and hence of fractal patterns. For the bilayer films containing larger Al grains, the nucleation rate of fractal patterns (Ge clusters) is faster and the number of patterns is larger.

Micro, Nano and Ultranano-Crystalline Diamond Deposition

2014 ◽  
Vol 802 ◽  
pp. 168-173 ◽  
Author(s):  
Divani C. Barbosa ◽  
M.R. Baldan ◽  
V.J. Trava-Airoldi ◽  
Evaldo Jose Corat
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Vapor ◽  
Peak Shift ◽  
X Ray Diffraction ◽  
Diamond Deposition ◽  
Induced Stress ◽  
Deposition Parameters ◽  
Hot Filament ◽  
Scanning Electron

This is a comparative experimental study of the micro, nanoand ultranano-crystalline diamond deposition. The Hot Filament Chemical Vapor Deposition (HFCVD) reactor deposits the films using different deposition parameters. Scanning Electron Microscopy and Field Emission Scanning Electron Microscopy let morphology inspection. Visible-Raman scattering loaded to estimating relative induced stress, by the graphite peak shift and associated with the defect incorporation and sp2bond enhancement. The x-ray diffraction confirmed the diamond crystallinity, where Scherrer ́s equations estimate crystallite size and diamond renucleation rates. In this work we propose a defect increasing relative graphite incorporation with the transition of micro, nanoto ultranano-crystalline diamond deposition. Besides this, we propose that this increase defects follows the increase diamond renucleation rates and decreases in the induced stress films. Included is a discussion of the possible reasons for these observations.

Effect of Bi Addition on the Electrochemical Behavior of Zinc Electrodes in Concentrated Alkaline Solutions

2013 ◽  
Vol 805-806 ◽  
pp. 1240-1249
Author(s):  
Hong Xia Liang ◽  
Fu Rong Li ◽  
Zhi Lin Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Linear Polarization ◽  
Electrochemical Behavior ◽  
Open Circuit Potential ◽  
Open Circuit ◽  
Exchange Current ◽  
Zinc Electrode ◽  
Current Densities ◽  
Scanning Electron

The electrochemical behavior of zinc electrode with bismuth addition in 35%KOH solutions has been investigated systematically by electrochemical methods including linear polarization, potentiostatic polarization, potential-time measurements at a constant current density, combining the observations of scanning electron microscopy (SEM). Linear polarization results showed that the open circuit potential shifted positively with increasing bismuth content, which is explained based on the gassing data and change in the exchange current of the zinc electrode. Addition of bismuth increased the exchange current of zinc reaction and caused an increase in the measured open circuit potential. Galvanostatic results showed that the addition of bismuth shortened the passivation time. Scanning electron microscopy images showed that the addition of bismuth aggravated the corrosion of zinc electrode which may be responsible for the increased tendency to passivation at high current densities. It has been found that at low current densities the reaction kinetics may be increased by addition of Bi, which is general agreement with the discharging test of actual alkaline batteries.

Effect of Nanocellulose Loading on Tensile Properties of Nitrile Rubber

2017 ◽  
Vol 264 ◽  
pp. 112-115
Author(s):  
Erfan Suryani Abdul Rashid ◽  
Wageeh Abdulhadi Yehye ◽  
Nurhidayatullaili Muhd Julkapli ◽  
Sharifah Bee O.A. Abdul Hamid
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Tensile Strength ◽  
Tensile Test ◽  
Tensile Properties ◽  
Mechanical Performance ◽  
Butadiene Rubber ◽  
Fracture Surfaces ◽  
Scanning Electron

Nanocellulose (NCC) is incorporated into nitrile butadiene rubber (NBR) latex with the composition 0 to 5 phr using dipping method. Mechanical properties of NBR/NCC composites using tensile test was used to characterize their mechanical performance and the fracture surfaces post tensile test were studied. The tensile strength of NBR/NCC composites increase significantly with the addition of nanocellulose. This could be anticipated due to the presence of Van der Waals interaction between hydrophilic natures of nanocellulose with hydrophobic of NBR consequently limits the tearing propagation. The result was supported with the fracture surfaces morphology viewed under Fourier Emission Scanning Electron Microscopy (FESEM).

Grain Size Effect on Lattice of Ni Nanocrystals Prepared Through Polyol Method

2008 ◽  
Vol 8 (8) ◽  
pp. 4127-4131 ◽  
Author(s):  
G. S. Okram ◽  
Kh. Namrata Devi ◽  
H. Sanatombi ◽  
Ajay Soni ◽  
V. Ganesan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Grain Size ◽  
Polyol Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Scanning Electron

Nanocrystalline nickel powders were prepared with grain size 'd' in the range 40–100 nm diameters through polyol method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used for characterization. XRD of the prepared samples consistently matched with standard fcc structure of nickel without any impurity peak. Detailed analysis and calculations using Scherrer equation for (111) peak revealed systematic increase in line width and peak shifting towards lower diffraction 2θ angles with decrease in nickel to ethylene glycol mole ratio. Different values of d estimated from various peaks of each sample suggested associated microstrains in the nanograins. Values of d estimated from X-ray diffraction patterns were compared with those obtained from atomic force microscopy and scanning electron microscopy results, and discussed. Observed lattice expansion is explained, on the basis of a theoretical model of linear elasticity.

Numerical Simulation and Experimental Analysis on the Crystal Growth of Excimer-Laser Crystallization of a-Si Film

2008 ◽  
Author(s):  
Long-Sun Chao ◽  
Yu-Ru Chen ◽  
Hsiun-Chang Peng
Keyword(s):  
Electron Microscopy ◽  
Numerical Simulation ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Grain Growth ◽  
Excimer Laser ◽  
Crystallographic Direction ◽  
Grain Distribution ◽  
Induced Crystallization ◽  
Scanning Electron

In this work, the excimer-laser-induced crystallization of amorphous silicon (a-Si) films was investigated numerically and experimentally. The basic structure is an a-Si film on a glass substrate. This study had investigated the effects of irradiating energy density on the grain size and structure by scanning electron microscopy (SEM). In the surface microstructure analysis of the laser-irradiated area, the critical fluences (full-melt threshold, FMT) between the partial melting and complete melting regimes can be found by applying scanning electron microscopy. An efficient two-dimensional numerical model is carried out to predict the critical fluences (FMT) and the transient temperature distribution during the laser processing. Numerical analysis of the temperature profile showed that a temperature drop occurred at the center of melted zone immediately after laser irradiation. From the analysis of temperature responses, the FMT obtained from the simulation results of the proposed model agree fairly well with those from the experimental data reported in the literature and acquired in this research. Furthermore, the grain growth of the poly-Si was studied by the grain observation of the cross section and its corresponding numerical simulation. The cross-sectional grain structure of the resulting poly-Si film was observed with different laser intensities. The grain sizes decreased with increasing irradiating energy intensity in the partial melting regime. From the surface observation, the grain distribution was uniform and most of the grain has a single crystallographic direction. The average grain size had the biggest value at FMT. But some super large grains occurred and combined with more than one crystallographic direction when the film obtained sufficiently high energy intensities that was closed or over the FMT. The grain distribution was not uniform. The super large gain was around the small grain size. The modified cellular automation method (MCA) was used to simulate the grain growth two-dimensionally and explain the grain development during the solidification process. The grain morphology of the numerical simulation was satisfied with the experimental observation. From the analysis of the grain growth, this model was able to simulate the undercooling effect and grain growth phenomenon and fitted for the experimental grain observation in the excimer-laser-induced crystallization.

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