Preparation and Characterization of Cr-Co-P Alloy Coating Electrodeposited from Trivalent Chromium Solution

2008 ◽  
Vol 373-374 ◽  
pp. 277-280
Author(s):  
Ye Ming Zhang ◽  
Da Jing Fang ◽  
Long Hao ◽  
An Lin ◽  
Fu Xing Gan
Keyword(s):  
Ph Value ◽  
Alloy Coating ◽  
Trivalent Chromium ◽  
Ammonium Citrate ◽  
Sodium Hypophosphite ◽  
Plating Bath ◽  
Electro Deposition ◽  
Iridium Dioxide ◽  
Pure Graphite

Cr-Co-P alloy coating was prepared from trivalent chromium bath and the appearance and performances of the coating were characterized. The Cr-Co-P alloy electroplating bath was prepared through orderly adding cobalt chloride, sodium hypophosphite monohydrate, urea, sodium format, ammonium citrate tribasic, boric acid, and ammonium brome into distilled water. Optimum plating crafts were determined as follows: pH value 1.5~3.0, temperature 25~45°C, plating time 1~15 minutes, and current density 5~25A·cm-2. Reticulate iridium dioxide coating electrode or highly pure graphite electrode were adopted as anode. And electro deposition experiments were carried out with air disturbance. The surfaces of deposited coatings are silvery white, bright and smooth. The Cr-Co-P alloy coatings were characterized by scanning electronic microscope (SEM). The results proved that P is favour to the improvement of deposit corrosion resistance. In addition, Cobalt atoms are in favor of enhancing throwing power and cover power of plating baths. Via adjusting plating bath, the electro-deposition rate could reach at 1.0~1.3μm·min-1, and the contents of P and Co could be controlled in 15~25% and 10~65%.

Formation and Structural Characterization of Electroless Ni-B-P Ternary Alloy Coatings

2014 ◽  
Vol 592-594 ◽  
pp. 385-390 ◽  
Author(s):  
P.G. Venkatakrishnan ◽  
S.S. Mohamed Nazirudeen ◽  
T.S.N. Sankara Narayanan
Keyword(s):  
Electroless Plating ◽  
Morphological Characteristics ◽  
Reducing Agents ◽  
Sodium Hypophosphite ◽  
Electron Microscopic ◽  
Plating Bath ◽  
Peak Broadening ◽  
Chloride Hexahydrate ◽  
Electroless Ni

The aim of the present investigation is to study the formation of electroless Ni-B-P alloy coatings and structural and morphological characterization of various coatings with different boron and phosphorous content. An alkaline plating bath with nickel chloride hexahydrate as the source of nickel ions and sodium borohydride and sodium hypophosphite as reducing agents were used for the formation of electroless Ni-B-P alloy coatings. The influence of changes in the concentrations of the reducing agents in the electroless plating bath on the chemical composition, structural and morphological characteristics of the coatings were studied. Scanning electron microscopic studies revealed that the surface morphology of Ni-B-P alloy coatings changed from corn cob-like structure to cauliflower-like structure with increasing borohydride concentration in electroless plating bath, whereas increase in hypophosphite concentration favoured sideway growth, thereby decreased the surface roughness of the Ni-B-P alloy coatings. The peak broadening in the X-Ray Diffraction profiles indicates the large reduction in the crystallite size of the electroless Ni-B-P alloy coatings with increasing boron content in the coating (i.e. for higher borohydride concentration in the plating bath).

Preparation and Characterization of Electroless Co-Ni Coated ZrO2 Powder for Microwave Absorbing

2010 ◽  
Vol 97-101 ◽  
pp. 1290-1294 ◽  
Author(s):  
Jing Hua Jiang ◽  
Fu Min Lu ◽  
Ai Bin Ma ◽  
Jin Zong Zuo ◽  
Yi Gao
Keyword(s):  
Ph Value ◽  
Weight Ratio ◽  
Average Weight ◽  
Network Analyzer ◽  
Absorption Properties ◽  
Plating Bath ◽  
Microwave Absorption Properties ◽  
Ni Alloy ◽  
Microwave Absorbing

Co-Ni coated ZrO2 composite powder was prepared by an optimized ultrasonic electroless plating process to obtain good microwave absorption properties in GHz region. Aggradation mechanism of electroless Co-Ni alloy was analyzed and the principal influencing factors on the depositing rate were investigated by weighting-in-powder. The metallized powder was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and vector network analyzer. Results showed that ultrafine ZrO2 powder pretreated with sensitization and activation were homogeneously deposited with Co-Ni coating at 358K and pH value of 9, immerged in the optimal plating bath using NaH2PO2 as reductant. The Co-Ni coating deposited in the alkaline plating bath had the depositing rate of above 6µm/h and the average weight ratio of 5.5 for Co/Ni. The new metallized powder was endowed high microwave absorbing properties; the maximum reflection loss reaches to -23dB at the frequency of 9.40 GHz.

Preparation and Properties of Electroless Deposited Ni-Sn-P Ternary Alloy Coatings

2011 ◽  
Vol 189-193 ◽  
pp. 455-460 ◽  
Author(s):  
Shao Feng Zhu ◽  
Yu Cheng Wu
Keyword(s):  
Ternary Alloy ◽  
Deposition Rate ◽  
Chloride Solution ◽  
Phosphorus Content ◽  
Ph Value ◽  
Alloy Coating ◽  
Stannic Chloride ◽  
Sodium Hypophosphite ◽  
Maximum Value ◽  
Tin Content

In this paper, Ni-Sn-P ternary alloy coating was prepared by the electroless depositing technique. Effects of tannic chloride, reductant and pH value of the bath on the coating were studied. And, erosion behavior of the coating in the 3.5g dm-1sodium chloride solution was also investigated. The results show that the electroless deposited Ni-Sn-P ternary alloy is amorphous. The deposition rate and the tin content in the coating increase, but the phosphorus content in the coating decreases with increasing the stannic chloride and sodium hypophosphite contents in the bath. The deposition rate increases with the pH value of the bath in the range of 3 to 6. Mass loss of the coating increases with increasing the erosion time and the flow velocity of erosion solution, which has its maximum value as the coating impacted at an angle of 60°.

Influence of temperature and pH value on deposition rate and corrosion resistance of Ni–Zn–P alloy coating

2019 ◽  
Vol 33 (01n03) ◽  
pp. 1940013
Author(s):  
Yongfeng Li ◽  
Chengguo Fu ◽  
Lili Liu ◽  
Mingchao Liang ◽  
Yaming Liu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Deposition Rate ◽  
Ph Value ◽  
Chemical Properties ◽  
Alloy Coating ◽  
Industrial Applications ◽  
Complexing Agent ◽  
Solution Ph ◽  
Plating Bath ◽  
The Stability

The Ni–Zn–P alloy coating has excellent physical and chemical properties that have been exploited for various industrial applications. Using sodium citrate as a complexing agent and lactic acid as a stabilizer, the effects of temperature and pH on the deposition rate and corrosion resistance of electroless plated Ni–Zn–P coating were studied. The results indicated that, when the temperature was 85[Formula: see text]C, a good deposition rate was obtained with stable plating solution. pH value of 9.0 is preferred for the coating process by considering the stability of plating bath and deposition rate. The Ni–Zn–P alloy coating deposited with plating temperature of 85[Formula: see text]C and bath pH of 9.0 has good quality, and a uniform and smooth surface texture without porosity.

Effect of Electro Deposition Parameters on Thickness and Fe Contents of Nickel-Iron Foam Alloys

2014 ◽  
Vol 1053 ◽  
pp. 41-49
Author(s):  
Xiao Min Huo ◽  
Gang He ◽  
Hong Yun Lin ◽  
Jian Li Wang ◽  
De Qing Wang
Keyword(s):  
Current Density ◽  
Ph Value ◽  
Nickel Foam ◽  
Energy Dispersive Spectrometer ◽  
Alloy Coating ◽  
Alloy Layer ◽  
Technological Parameters ◽  
Electro Deposition ◽  
Nickel Iron ◽  
Deposition Parameters

An Ni-Fe alloy on the surface of nickel foam was prepared by electro deposition. The effects of technological parameters including current density, pH value, temperature and the ratio of [Ni2+] to [Fe2+] of planting solution on the thickness and iron content of the alloy coating were studied. The cross-section microstructure and surface morphologies were observed by optical microscopy and scanning electron microscope, and the compositions of the alloy coating were analyzed by energy dispersive spectrometer and ICP-AES. Experiment results show that the thickness of the alloy coating is increased with increasing current density, temperature, pH value and the ratio of [Ni2+] to [Fe2+] of the planting solution. The Fe contents of the alloy coating is increased with increasing current density and pH value of the planting solution, and decreased with increasing temperature and the ratio of [Ni2+] to [Fe2+] of the planting solution. A 36.2 μm thick alloy layer of uniform and dense coating with the Fe content of 60.5 wt% is obtained under the parameters ofn(Ni2+)/n(Fe2+)= 4, current density = 10 A/dm2and pH = 4.2 at 50 °C for one hour.

scholarly journals The Characterization of Co-Ni-Fe Coating in Different pH Environment

2019 ◽  
Vol 8 (4) ◽  
pp. 6950-6955
Keyword(s):  
Ph Value ◽  
Strong Acid ◽  
Alloy Coating ◽  
Weak Acid ◽  
Corrosion Performance ◽  
High Corrosion Resistance ◽  
Electrodeposition Process ◽  
High Microhardness ◽  
Coating Alloy

This study aims to produce a Co-Ni-Fe alloy coating on a mild steel hollow cylinder shape by electrodeposition process and analyze the effect of different pH on the corrosion performance of the alloy coating. During the electrodeposition process, the temperature and time are set to 50°C and 30 minutes, respectively. Different pH value consisting of pH 2.1 (strong acid), 5.2 (weak acid), 6.9 (neutral), 8.4 (weak alkali) and 12.3 (strong alkali) are used. From the results obtained it was found that the deposited Co-Ni-Fe alloy has excellent corrosion performance. Corrosion rate obtained for strong acid, weak acid, neutral, weak alkali and strong alkali are 5.88 mmpy, 2.95 mmpy, 1.17 mmpy, 2.16 mmpy and 5.72 mmpy, respectively. Hence this studied showed that Co-Ni-Fe coating alloy could be used as an alternative to prevent against corrosion due to its high corrosion resistance as well as high microhardness.

scholarly journals Microscopic Image Segmentation and Morphological Characterization of Novel Chitosan/Silica Nanoparticle/Nisin Films Using Antimicrobial Technique for Blueberry Preservation

Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 303
Author(s):  
Rokayya Sami ◽  
Schahrazad Soltane ◽  
Mahmoud Helal
Keyword(s):  
Ph Value ◽  
Silica Nanoparticle ◽  
Morphological Characterization ◽  
Aerobic Bacteria ◽  
Nano Materials ◽  
Elongation At Break ◽  
Stable Suspension ◽  
Average Size ◽  
Material Ductility

In the current work, the characterization of novel chitosan/silica nanoparticle/nisin films with the addition of nisin as an antimicrobial technique for blueberry preservation during storage is investigated. Chitosan/Silica Nanoparticle/N (CH-SN-N) films presented a stable suspension as the surface loads (45.9 mV) and the distribution was considered broad (0.62). The result shows that the pH value was increased gradually with the addition of nisin to 4.12, while the turbidity was the highest at 0.39. The content of the insoluble matter and contact angle were the highest for the Chitosan/Silica Nanoparticle (CH-SN) film at 5.68%. The use of nano-materials in chitosan films decreased the material ductility, reduced the tensile strength and elongation-at-break of the membrane. The coated blueberries with Chitosan/Silica Nanoparticle/N films reported the lowest microbial contamination counts at 2.82 log CFU/g followed by Chitosan/Silica Nanoparticle at 3.73 and 3.58 log CFU/g for the aerobic bacteria, molds, and yeasts population, respectively. It was observed that (CH) film extracted 94 regions with an average size of 449.10, at the same time (CH-SN) film extracted 169 regions with an average size of 130.53. The (CH-SN-N) film presented the best result at 5.19%. It could be observed that the size of the total region of the fruit for the (CH) case was the smallest (1663 pixels), which implied that the fruit lost moisture content. As a conclusion, (CH-SN-N) film is recommended for blueberry preservation to prolong the shelf-life during storage.

Preparing Process and Properties of Collagen Modified Cotton Fiber

2011 ◽  
Vol 236-238 ◽  
pp. 1415-1419 ◽  
Author(s):  
Yun Hui Xu ◽  
Zhao Fang Du
Keyword(s):  
Cotton Fiber ◽  
Treatment Time ◽  
Ph Value ◽  
Periodate Oxidation ◽  
Aqueous Acetic Acid ◽  
Collagen Concentration ◽  
Acid Media ◽  
Xps Characterization ◽  
Aldehyde Groups

In order to develop cotton fabric underwear with the health care function, the cotton fiber was modified with the collagen (CMCF) using periodate oxidation method. The aldehyde groups on the glucose chains of the oxidized cotton cellulose were reacted with the amino groups of collagen to obtain the CMCF, and the oxidized cellulose was crosslinked with collagen in aqueous acetic acid media. The effects of collagen concentration, treatment time, reaction temperature, pH value of solution and periodate concentration on the amount of collagen crosslinked on cotton fiber were respectively discussed, and the optimal reaction technology was obtained. XPS characterization of the modified cotton fiber showed a characteristic peak about 400.0–405.0 eV corresponding to collagen, which indicated that the collagen was combined on the surface of cotton fiber. The mechanical properties of the collagen modified cotton fiber were improved. The resulting CMCF is a new natural ecological fiber and has the extensive application as a carrier for the controlled release of drugs.

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