The Preparation and Growth Mechanism of Ni-Coated TiH2 Composite Powder by Electroless Plating

2013 ◽  
Vol 743-744 ◽  
pp. 353-359 ◽  
Author(s):  
Jia Qian Hou ◽  
Lai Rong Xiao ◽  
Lei Guo ◽  
Song Song Zhou ◽  
Ruo Fan Wang
Keyword(s):  
Growth Mechanism ◽  
Electroless Plating ◽  
Composite Powder ◽  
Ostwald Ripening ◽  
Ph Value ◽  
Orthogonal Experiment ◽  
Layer Growth ◽  
X Ray Diffraction ◽  
Powder Morphology ◽  
Technical Parameters

The Ni-coated TiH2composite powder was prepared by electroless plating and the concentration of reducing agent, reaction temperature, reaction time, PH value and so on were optimized by orthogonal experiment design. The Ni/TiH2composite powder morphology and composition was analyzed by scanning electron microscopy (SEM), Energy Dispersive spectroscopy (EDS), X-ray diffraction (XRD); the plated Ni layer growth mechanism was explored preliminary. The Optimization technical parameters: the plating temperature was 85, the pH value was 10 and the hydrazine concentration was 100ml/L. Complete coating and uniform thickness of the Ni layer with average coating thickness about 2.0μm was successfully prepared with the optimization technical parameters. The growth mechanism of the coating followed the Ostwald ripening mechanism. Compared the TiH2uncoated with Ni layers particles, the TiH2composite powder could efficiently delay the starting time of gas release by approximately 80s.

Preparation of Ni-Coated SiC Ceramic Composite Powder by Electroless Plating

2011 ◽  
Vol 117-119 ◽  
pp. 77-80
Author(s):  
Huai Yao ◽  
Guang Lin Zhu ◽  
Yong Zhi Wang
Keyword(s):  
Electroless Plating ◽  
Ph Value ◽  
Nickel Chloride ◽  
Gas Production ◽  
Basic Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Deep Blue ◽  
Reaction Theory ◽  
Diffraction Patterns

As a surface technology, electroless plating is applied to almost every industry branch. To improve the wettability of SiC powder and metal, the surface of SiC powders was plated with a Ni plating in the basic solution according to the reaction theory of electroless plating. The main salting was nickel chloride, and the reducing agent was hydrazine hydrate. The plating velocity, phase transformation and microstructurewere investigated using XRD and SEM. The results show that the SiC powders had no increasing weight and no reaction can occur when the pH below 8.5. when the pH value was between 10 and 11, the weight gain of powders closed to the theoretical value, the Ni peaks in X-ray diffraction patterns of powders was relatively strong, the SiC coating surface was composed of granular, cellular and globe-like Ni, the substrate was covered of Ni plating completely. When the pH value was above 11, the gas production was becoming more pronounced and the reaction speed increasing with the increased of the pH value, the time from deep blue to colorless of solution started to drop off, the Ni(OH)2peaks in X-ray diffraction patterns of powders have already begun to emerged and a small amount of nickel films was generated.

Synthesis Conditions of Nano-Hydroxyapatite Using Chondroitin Sulfate by Co-Precipitation Method

2011 ◽  
Vol 236-238 ◽  
pp. 2076-2079
Author(s):  
Yan Rong Sun ◽  
Tao Fan ◽  
Yong Huang ◽  
Li Guo Ma ◽  
Feng Liu
Keyword(s):  
Chondroitin Sulfate ◽  
Ph Value ◽  
Orthogonal Design ◽  
Precipitation Method ◽  
Synthesis Process ◽  
X Ray Diffraction ◽  
Powder Morphology ◽  
Synthesis Conditions ◽  
Transmission Electron ◽  
Co Precipitation

The introduction of biomineralization was coupled with the co-precipitation synthesis process of nano-hydroxyapatite with the addition of chondroitin sulfate as a template agent. The effect of a variety of processing conditions on the properties of final hydroxyapatite (HA) product was investigated by orthogonal design. The ratio of calcium to phosphorus was detected by chemical analysis, the phase composition was evaluated by X-ray diffraction (XRD), and the powder morphology was characterized by transmission electron microscope (TEM). The process scheme, moreover, was optimized by the analysis of four aspects which may have different extent of influence on product properties. It can be concluded from the results that product properties can be affected remarkably by the content of chondroitin sulfate and the pH value of reactant, less remarkably by the reaction temperature and slightly by the reaction time.

The Process of Electroless Plating Ni on the Surface of Carbon Fibers

2010 ◽  
Vol 97-101 ◽  
pp. 1484-1488 ◽  
Author(s):  
Xian Feng Xu ◽  
Peng Xiao ◽  
Jia Sun
Keyword(s):  
Electron Microscope ◽  
Cross Section ◽  
Carbon Fibers ◽  
Chemical Reaction ◽  
Electroless Plating ◽  
Alloy Layer ◽  
Layer Growth ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

Carbon fibers had been modified by the method of electroless plating Ni. The surface morphology, ingredient and cross-section images of modification carbon fibers were charactered by scanning electron microscope and X-ray diffraction. A continuous dense Ni-P alloy layer could be coated on the surface of carbon fibers by such method. The nickel-plated layer expanded in a layer growth pattern. The reaction thermodynamic analysis indicated that the process was spontaneous. The controlling process of electroless plating Ni on the carbon fibers could be divided into 3 stages: at first, controlled by chemical reaction; hereafter, controlled by chemical reaction and ions diffusion; finally, controlled by ions diffusion.

PREPARATION OF ULTRAFINE W–Cu COMPOSITE POWDER USING ULTRASONIC-ASSISTED ELECTROLESS PLATING

2013 ◽  
Vol 27 (19) ◽  
pp. 1341004 ◽  
Author(s):  
LIMEI HUANG ◽  
LAIMA LUO ◽  
XIAOYU DING ◽  
XIANG ZAN ◽  
YU HONG ◽  
...  
Keyword(s):  
Growth Mechanism ◽  
Electroless Plating ◽  
High Performance ◽  
Room Temperature ◽  
Composite Powder ◽  
Surface Defects ◽  
Cell Structure ◽  
Reduction Reaction ◽  
Composite Powders ◽  
Ultrasonic Assisted

W – Cu ultrafine/nanocomposite powders have high sintering activity, so ultrafine/nanotechnology of W – Cu composite powders is one of the main methods to obtain fully dense, high-performance W – Cu composite materials. Cu -coated ultrafine W composite powders were synthesized by ultrasonic-assisted electroless plating process with non-noble metal activation pretreatment at room temperature in this paper. The growth mechanism of Cu layers and surface morphologies and composition of initial ultrafine W powders, pretreated W powders and Cu -coated W powders were analyzed by field emission scanning electron microscopy (FE-SEM), and energy dispersion spectrometry (EDS). The results show that the uniformly Cu coated W composite powder is successfully synthesized without conventional sensitization and activation steps by ultrasonic-assisted electroless plating at room temperature. The Cu layers on the ultrafine W powders had cell structure with dense, uniform distribution. The growth mechanism of Cu layers appears as follows: the surfaces of pretreated W powders appear linear-like and lamellar-like surface defects which act as activated sites. The reactants in the plating solution were adsorbed on catalytic activity surfaces of powders and happened oxidation–reduction reaction. The growth and aggregation mechanisms of Cu particles after nucleation are stripy Cu -cells grew up, bend, bifurcated, and aggregated, then wounding into a cellular structure, like "wrapping wool clusters" in the life. Finally, Cu cells grow up and merge into a layer.

The Research on Technology of Electroless Ni-W-P Ternary Alloys Plating on the Aluminium Alloy

2011 ◽  
Vol 117-119 ◽  
pp. 1338-1342 ◽  
Author(s):  
Huai Yao ◽  
Guang Lin Zhu ◽  
Meng Du
Keyword(s):  
Heat Treatment ◽  
Aluminium Alloy ◽  
Electroless Plating ◽  
Ph Value ◽  
Surface Hardness ◽  
Average Diameter ◽  
Ternary Alloys ◽  
X Ray Diffraction ◽  
To Come ◽  
Electroless Ni

To improve the surface hardness，corrosion resistance and wear resistance of the coating substrate, the ternary Ni-W-P alloy coatings were deposited on H12 aluminium alloy by electroless plating. The microstructure, phase transformation, plating velocity and hardness were investigated with X-ray diffraction technique, scanning electron microscope and differential thermal analysis. The results showed that when the PH value of electroless plating solution was 9.0 and the temperature of solution was 85°C, after 3h electroless plating, the substrate was completely covered by Ni-W-P plating, the surface was composed of uniform crystalline grains, their average diameter was about 7μm and they had no obvious defects, the contents of W reached up to 9.60%, and the hardness attained 610HV. In the temperature range of 75-90 °C, the plating rate has been increasing with temperature, when the temperature reached 90 °C, the plating rate reached as high as 13μm / h. When the temperature of heat treatment reached 336°Cfor 1h, the crystallization of Ni3P on the surface began to come into being. The maximum hardness of Ni-W-P plating was up to 920HV after heat treatment at 380 °Cfor 1h.

Research on Anti-Felting Finishing Process of Wool Knitted Fabric with Protease

2011 ◽  
Vol 383-390 ◽  
pp. 5492-5495 ◽  
Author(s):  
Hua E Wang
Keyword(s):  
Ph Value ◽  
Orthogonal Experiment ◽  
Acid Protease ◽  
Process Conditions ◽  
Knitted Fabric ◽  
Optimal Process ◽  
Technical Parameters ◽  
Finishing Process ◽  
Protease Treatment ◽  
Energy Saving Technology

In this paper, acid protease treatment was studied on anti-felting finishing of wool knitted fabric and the optimal process conditions were obtained by orthogonal experiment. The technical parameters were hydrogen peroxide concentration 40mL/L, temperature 45°C, time 45min, pH value 8, concentration of protease 5 % (owf), pH value 5, temperature 40°C and time 35min. Through this process, the felt resistance property of wool knitted fabric has been improved greatly. Because of low temperature, energy consumption, environmental pollution, this process belongs to environmental protection and energy saving technology.

Process Optimization Studies Based on BP Neural Network in Electroless Plating of Ni-Fe-Co-P on Carbon Fiber

2012 ◽  
Vol 616-618 ◽  
pp. 1978-1983
Author(s):  
Ying Jia ◽  
Hu Xu ◽  
Cheng Feng ◽  
Xing Yun Wang
Keyword(s):  
Neural Network ◽  
Carbon Fiber ◽  
Electroless Plating ◽  
Bp Neural Network ◽  
Ph Value ◽  
Orthogonal Experiment ◽  
Predictive Ability ◽  
Sodium Hypophosphite ◽  
Experimental Program ◽  
Method Of Calculation

It presents a method to predict and optimize the electroless plating process, and to compare the predictive ability of the network to the experimental results. It combined with the neural network and orthogonal experiment and used a small step searching method to optimize the chemical process of plated Ni - Co-Fe-P on carbon fiber within the scope of the process parameters, got more optimized process recipe: the temperature is 88°C, ratio of the main salt concentration is 0.46, the concentration of sodium citrate is 46 g/L, and the pH value is 9.03, the concentration of sodium hypophosphite is 24 g/L. Through validating with experiments, the error between them is 2.39%, the linear correlation between the method of calculation and experimental program of the target is very good, and the correlation coefficient R =0.99943 which indicated that the training results are reliable and the BP neural network optimizing the process recipe is indeed feasible.

Growth Mechanism of Copper Oxide Fabricaticated by Potentiostatic Electrodeposition Method

2017 ◽  
Vol 890 ◽  
pp. 303-307 ◽  
Author(s):  
Nurliyana binti Mohamad Arifin ◽  
Fariza Mohamad ◽  
Chia Hui Ling ◽  
Nabiah binti Zinal ◽  
Asyikin Sasha binti Mohd Hanif ◽  
...  
Keyword(s):  
Thin Film ◽  
Growth Mechanism ◽  
Deposition Time ◽  
Ph Value ◽  
Copper Acetate ◽  
Bath Temperature ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Potentiostatic Electrodeposition

This experiment is about fabrication of n-type Cu2O thin film on fluorine doped thin oxide (FTO) glass by using copper acetate based solution through potentiostaticelectrodeposition. A range of deposition time was carried out from 20 to 40 minutes and the results were obtained. The other parameters such as potential deposition, bath temperature and pH value of solution were kept constant for-0.125Vvs Ag/AgCl, 60 °C and pH 6.3, respectively. It was found that the optimum deposition time for growth mechanism of n-type Cu2O thin film was 30 minutes. Structural, morphologicaland optical properties were characterized by using X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FE-SEM), and Ultraviolet and visible Absorption Spectroscopy (UV-Vis), respectively. The successfully fabrication of n-Cu2O was confirmed using PEC measurement result.

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.

scholarly journals Zeolite NaP1 Functionalization for the Sorption of Metal Complexes with Biodegradable N-(1,2-dicarboxyethyl)-D,L-aspartic Acid

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2518
Author(s):  
Dorota Kołodyńska ◽  
Yongming Ju ◽  
Małgorzata Franus ◽  
Wojciech Franus
Keyword(s):  
Experimental Data ◽  
Aspartic Acid ◽  
Ph Value ◽  
Complexing Agents ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Modified Zeolite ◽  
X Ray ◽  
Slow Release Fertilizers ◽  
Pseudo Second Order

The possibility of application of chitosan-modified zeolite as sorbent for Cu(II), Zn(II), Mn(II), and Fe(III) ions and their mixtures in the presence of N-(1,2-dicarboxyethyl)-D,L-aspartic acid, IDHA) under different experimental conditions were investigated. Chitosan-modified zeolite belongs to the group of biodegradable complexing agents used in fertilizer production. NaP1CS as a carrier forms a barrier to the spontaneous release of the fertilizer into soil. The obtained materials were characterized by Fourier transform infrared spectroscopy (FTIR); surface area determination (ASAP); scanning electron microscopy (SEM-EDS); X-ray fluorescence (XRF); X-ray diffraction (XRD); and carbon, hydrogen, and nitrogen (CHN), as well as thermogravimetric (TGA) methods. The concentrations of Cu(II), Zn(II), Mn(II), and Fe(III) complexes with IDHA varied from 5–20 mg/dm3 for Cu(II), 10–40 mg/dm3 for Fe(III), 20–80 mg/dm3 for Mn(II), and 10–40 mg/dm3 for Zn(II), respectively; pH value (3–6), time (1–120 min), and temperature (293–333 K) on the sorption efficiency were tested. The Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin adsorption models were applied to describe experimental data. The pH 5 proved to be appropriate for adsorption. The pseudo-second order and Langmuir models were consistent with the experimental data. The thermodynamic parameters indicate that adsorption is spontaneous and endothermic. The highest desorption percentage was achieved using the HCl solution, therefore, proving that method can be used to design slow-release fertilizers.

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