EFFECT OF STIRRING RATE ON ELECTROCHEMICAL CODEPOSITION OF Ni-SiC COMPOSITE

Nickel-Silicon Carbide (Ni-SiC) composite has been prepared by electrochemical codeposition technique. Nickel sulfamate bath was used along with grain modifier saccharine and cationic surfactant cetyltrimetylammonium bromide (CTAB). The effect of stirring rate was systematically studied and optimized to get well dispersed SiC particles in appropriate amount. Mixed crystalline phase with reinforced [2 1 1] crystal orientation was obtained by XRD analysis. The result revealed that, 250 revolutions per minute (rpm) is optimum stirring rate for the electrochemical codeposition of Ni–SiC. Coating prepared at 250 rpm showed highest microhardness and lowest coefficient of friction with better surface morphology and well distributed nano SiC particles.Scientific World, Vol. 12, No. 12, September 2014, page 30-33

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Effect of Current Density on Properties Of Nickel-Silicon Carbide Composites

Journal of Institute of Science and Technology ◽

10.3126/jist.v21i1.16055 ◽

2016 ◽

Vol 21 (1) ◽

pp. 82-85

Author(s):

Kailash Hama ◽

Armila Rajbhandari Nyachhyon ◽

Gobinda Gyawali ◽

Soo Wohn Lee

Keyword(s):

Silicon Carbide ◽

Coefficient Of Friction ◽

Current Density ◽

Surface Texture ◽

Cetyltrimethylammonium Bromide ◽

Deposition Technique ◽

Regular Surface ◽

Homogeneous Surface ◽

Nickel Silicon ◽

Sulfamate Bath

Nickel-Silicon Carbide (Ni-SiC) composite coating has been prepared by two electrode electrochemical co-deposition technique in nickel sulfamate bath. The Cetyltrimethylammonium bromide (CTAB) was added in bath as cationic surfactant whereas saccharine as a grain modifier. The effect of current density during deposition was systematically studied and optimized to get homogeneous surface texture with utmost microhardness and deprived coefficient of friction. The result revealed that 60 mA/cm2 current density was found to be the optimum current density which showed the highest microhardness of 590 ± 10 Hv and lowest coefficient of friction with regular surface morphology.Journal of Institute of Science and TechnologyVol. 21, No. 1, 2016, Page : 82-85

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Hard Coating Materials Based on Photo-Reactive Silsesquioxane for Flexible Application: Improvement of Flexible and Hardness Properties by High Molecular Weight

Polymers ◽

10.3390/polym13101564 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1564

Author(s):

Jong Tae Leem ◽

Woong Cheol Seok ◽

Ji Beom Yoo ◽

Sangkug Lee ◽

Ho Jun Song

Keyword(s):

Molecular Weight ◽

Surface Morphology ◽

High Molecular Weight ◽

Sol Gel ◽

Xrd Analysis ◽

Polyhedral Oligomeric Silsesquioxanes ◽

Coating Materials ◽

Pencil Hardness ◽

Coated Film ◽

Flexible Application

EPOSS of polyhedral oligomeric silsesquioxanes (POSS) mixture structure and LPSQ of ladder-like polysilsesquioxane (LPSQ) structure were synthesized via sol–gel reaction. EPSQ had a high molecular weight due to polycondensation by potassium carbonate. The EPSQ film showed uniform surface morphology due to regular double-stranded structure. In contrast, the EPOSS-coated film showed nonuniform surface morphology due to strong aggregation. Due to the aggregation, the EPOSS film had shorter d-spacing (d1) than the EPSQ film in XRD analysis. In pencil hardness and nanoindentation analysis, EPSQ film showed higher hardness than the EPOSS film due to regular double-stranded structure. In addition, in the in-folding (r = 0.5 mm) and out-folding (r = 5 mm) tests, the EPSQ film did not crack unlike the EPOSS coated film.

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Mechanical properties of nickel silicon carbide nanocomposites

Materials Science and Engineering A ◽

10.1016/s0921-5093(01)01692-6 ◽

2002 ◽

Vol 328 (1-2) ◽

pp. 137-146 ◽

Cited By ~ 206

Author(s):

A.F. Zimmerman ◽

G. Palumbo ◽

K.T. Aust ◽

U. Erb

Keyword(s):

Mechanical Properties ◽

Silicon Carbide ◽

Nickel Silicon

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Study on Electrodeposition of Ni-Graphite Composite Coatings in Sulfamate Bath

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.150-151.1546 ◽

2010 ◽

Vol 150-151 ◽

pp. 1546-1550 ◽

Cited By ~ 3

Author(s):

Xiang Zhu He ◽

Xiao Wei Zhang ◽

Xin Li Zhou ◽

Zhi Hong Fu

Keyword(s):

Surface Morphology ◽

Process Parameters ◽

Current Density ◽

Graphite Particle ◽

Particle Concentration ◽

Composite Coatings ◽

Nickel Matrix ◽

Graphite Composite ◽

Surface Morphologies ◽

Sulfamate Bath

This paper presented the composite coatings of nickel with graphite particle on the aluminum substrate using a nickel sulfamate bath. Effects of graphite particle concentration on the surface morphologies of the composite coatings were investigated. The inclusion of graphite particle into metal deposits was dependent on many process parameters, including particle concentration, current density, pH and temperature. Results of SEM and XRD demonstrated that graphite particle had successfully deposited on that nickel matrix; besides, the surface morphology of coatings obtained from sulfamate bath containing 2g/L graphite particle dispersed more uniformly than the ones with higher concentration.

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Microwave Synthesis of Silicon Carbide Nano Powders with Silicon and Carbon

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.118 ◽

2014 ◽

Vol 602-603 ◽

pp. 118-121

Author(s):

You Jun Lu ◽

Hong Fang Shen ◽

Sheng Wei Guo

Keyword(s):

Silicon Carbide ◽

Particle Size ◽

Microwave Heating ◽

Chemical Reaction ◽

Crystalline Phase ◽

Microwave Synthesis ◽

Time Effects ◽

Xrd Patterns

Nanosized silicon carbide powders were synthesized from a mixture of silicon and carbon by microwave heating methods. The Result Indicates SiC can be formed at lower temperatures by using the Si-C reaction at 1200°C for 30min. XRD patterns shows that SiC peaks appeared as the only crystalline phase. SEM photo shows the particle size was 100～200 nanometer. At the same time, Effects of chemical reaction of silicon and carbon was researched by mechanical activated microwave synthesis.

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Surface Structure and Cells Adhesion on Doped Polyethylene

Materials Science Forum ◽

10.4028/www.scientific.net/msf.567-568.253 ◽

2007 ◽

Vol 567-568 ◽

pp. 253-256

Author(s):

Regina Mikulíková ◽

Kateřina Kolářová ◽

Václav Švorčík ◽

Barbora Dvořánková ◽

Tomáš Sopuch

Keyword(s):

Surface Morphology ◽

Ftir Spectroscopy ◽

Crystalline Phase ◽

Film Surface ◽

Surface Wettability ◽

Oxidized Cellulose ◽

3T3 Fibroblasts ◽

Doped Polymer

The properties of polyethylene doped with Ca2+ salt of oxidized cellulose was studied by different techniques. FTIR spectroscopy was used for the determination of crystalline phase in polymer film, surface wettability was determined by standard goniometry and surface morphology was examined by SEM microscopy. Adhesion of mouse 3T3 fibroblasts on the doped polymer was studied in vitro. It was found that the polyethylene doped with the cellulose derivative can be sterilized in boiling water. The number and homogeneity of adhering cells were shown to depend on the surface wettability and morphology.

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THE EFFECT OF PREPARED PARAMETERS ON THE MICROSTRUCTURE OF ELECTRODEPOSITED NANOCRYSTALLINE NICKEL COATING

Surface Review and Letters ◽

10.1142/s0218625x04006414 ◽

2004 ◽

Vol 11 (04n05) ◽

pp. 433-442 ◽

Cited By ~ 8

Author(s):

C. Y. DAI ◽

Y. PAN ◽

S. JIANG ◽

Y. C. ZHOU

Keyword(s):

Grain Size ◽

Surface Morphology ◽

Current Density ◽

Crystal Orientation ◽

Nickel Coating ◽

Pulse Frequency ◽

Lattice Parameter ◽

Nanocrystalline Nickel ◽

Peak Current Density ◽

Peak Current

The nanocrystalline nickel coating was synthesized by pulse-jet electrodeposition from modified Watts bath. Pulse and jet plating was employed to increase the deposition current density, decrease diffusion layer, increase the nucleation rate and in this case the prepared method would result in fine-grained deposits. Transmission and scanning electron microscopy and X-ray diffraction (XRD) were used to study the microstructure, the surface morphology, the crystal preferred orientation and the variety of the lattice parameter respectively. The influence of pulse parameters, namely peak current density, the duty cycle and pulse frequency on the grain size, surface morphology, crystal orientation and microstructure was studied. The results showed that with increasing peak current density, the deposit grain size was found to decrease markedly in other parameters at constant. However, in our experiment it was found that the grain size increased slightly with increasing pulse frequency. For higher peak current density, the surface morphology was smoother. The crystal orientation progressively changed from an almost random distribution to a strong (111) texture. This means that the peak current density was the dominated parameter to effect the microstructure of electrodeposited nanocrystalline nickel coating. In addition, the lattice parameter for the deposited nickel is calculated from XRD and it is found that the calculated value is less than the lattice parameter for the perfect nickel single crystal. This phenomenon is explained by the crystal lattice mismatch.

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Stabilizing the surface morphology of Si[sub 1−x−y]Ge[sub x]C[sub y]/Si heterostructures grown by molecular beam epitaxy through the use of a silicon-carbide source

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena ◽

10.1116/1.590111 ◽

1998 ◽

Vol 16 (4) ◽

pp. 1937 ◽

Cited By ~ 6

Author(s):

E. T. Croke

Keyword(s):

Silicon Carbide ◽

Molecular Beam Epitaxy ◽

Surface Morphology ◽

Molecular Beam

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Crystal Orientation and Surface Morphology of Sono-Electroplated Zinc Film from Alkali Zincate Bath

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.1743 ◽

2009 ◽

Vol 79-82 ◽

pp. 1743-1746

Author(s):

Atsushi Chiba

Keyword(s):

Surface Morphology ◽

Current Efficiency ◽

Compressive Stress ◽

Diffusion Layer ◽

Current Density ◽

Crystal Orientation ◽

Shearing Stress ◽

Thickness Of Diffusion Layer ◽

Zincate Solution

Zn plated on Cu plate from 0.65 mol/dm3 alkali zincate solution in 8 mol/dm3 KOH bath Electrolysis was carried out as current density of 10 - 100 mA/cm2. The sonication was prepared 40 kHz. The current efficiency was 76.1 % at 10 mA/cm2 in 0.10 mol/dm3 zincate and 100 % in 0.15 mol/dm3 zincate at 50 mA/cm2. The current efficiency and thickness of diffusion layer affected with the agitation of micro-jet. Surface of film was smooth and dense as particle crushed down with the shockwave pressure. (112) plane moved horizontally to <113> direction under the compressive stress or shearing stress.

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Direct Observation of Dielectric Breakdown at Step-Bunching on 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.821-823.468 ◽

2015 ◽

Vol 821-823 ◽

pp. 468-471 ◽

Cited By ~ 2

Author(s):

Yuki Mori ◽

Mieko Matsumura ◽

Hirotaka Hamamura ◽

Toshiyuki Mine ◽

Akio Shima ◽

...

Keyword(s):

Silicon Carbide ◽

Surface Morphology ◽

Dielectric Breakdown ◽

Optical Emission ◽

Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

Tem Analysis ◽

Mos Capacitor ◽

Step Bunching ◽

Electrical Stress

The mechanism of dielectric breakdown of oxide on step-bunching of 4H-silicon carbide (SiC) was investigated. Comparing the surface morphology obtained before forming metal-oxide-semiconductor (MOS) capacitor and optical emission on the capacitor under electrical stress, it was cleared that current concentrates on step-bunching and it often caused preferential dielectric breakdown. Based on TEM analysis and the observation of time dependence of emission under the stress, a new model was proposed to explain the dielectric breakdown on step-bunching.

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