scholarly journals Microstructure and Corrosion Resistance of WC-Based Cermet/Fe-Based Amorphous Alloy Composite Coatings

Coatings ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 393 ◽  
Author(s):  
Liping Xu ◽  
Jinbing Song ◽  
Xiaofeng Zhang ◽  
Changguang Deng ◽  
Min Liu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Amorphous Alloy ◽  
Composite Coating ◽  
Composite Coatings ◽  
Alloy Composite ◽  
Electrochemical Tests ◽  
Transmission Electron ◽  
Alkaline Electrolytes ◽  
Naoh Solution ◽  
Corrosive Environments

There is an urgent need to improve the corrosion resistance of WC-based cermet coatings in different corrosive environments. The main objective of this work was to investigate the microstructure and evaluate the corrosion resistance in neutral, acidic, and alkaline electrolytes of the WC-based cermet/Fe-based amorphous alloy composite coating. Thus, a composite coating of WC–CoCr/Fe-based amorphous alloy and a single WC–CoCr coating were fabricated using the high-velocity oxygen fuel (HVOF) process. The phase composition, microstructure of the original powders, and as-sprayed coatings were studied. The detailed interface information between different compositions of the composite coating was observed by high-resolution transmission electron microscopy (HRTEM). The corrosion resistance of the coatings was studied comparatively by electrochemical tests in 3.5 wt % NaCl, 1 M HCl and 1 M NaOH solutions, respectively. Results showed that the composited coating had a dense layered structure with a composition of WC, Fe-based amorphous alloy, and small amount of W2C. It was revealed that obvious inter-diffusion exists between the interfaces of tungsten carbide/Co, Cr binder and WC–CoCr/Fe-based amorphous alloy. The electrochemical test results showed that the composite coating displayed better corrosion resistance than single WC–CoCr coating both in 3.5 wt % NaCl solution and in 1 M NaOH solution.

MICROSTRUCTURE AND ELECTROCHEMICAL PROPERTIES OF Ni–B/GO ULTRASONIC-ASSISTED COMPOSITE COATINGS

2019 ◽  
Vol 26 (10) ◽  
pp. 1950080
Author(s):  
JIBO JIANG ◽  
HAOTIAN CHEN ◽  
LIYING ZHU ◽  
YAOXIN SUN ◽  
WEI QIAN ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Composite Coatings ◽  
Ultrasonic Field ◽  
Protective Material ◽  
X Ray ◽  
Electrochemical Tests ◽  
Ultrasonic Assisted ◽  
Corrosive Environments

Graphene oxide (GO) sheet and ultrasonic field (UF) were successfully employed to produce Ni–B/GO and UF–Ni–B/GO composite coatings on Q235 mild steel by electroless plating. The composite coatings’ structure and surface morphology were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Results showed that GO was successfully co-deposited in the Ni–B alloy. Moreover, UF–Ni–B/GO composite coatings have smoother surface and thicker cross-section than others. The microhardness and corrosion resistance of the sample coatings were determined using Vickers hardness tests, Tafel electrochemical tests and electrochemical impedance measurements (EIS) in 3.5[Formula: see text]wt.% NaCl solution to receive the effect of GO and ultrasonic. The findings indicated that UF–Ni–B/GO exhibited optimum hardness (856[Formula: see text]HV) and enhanced corrosion resistance (6.38 [Formula: see text][Formula: see text] over the Ni–B and Ni–B/GO coatings. Due to these interesting properties of the coating, it could be used as a protective material in the automotive and aerospace industries for parts of machines that were manipulated in high temperature and corrosive environments.

scholarly journals Glass-Forming Ability and Corrosion Resistance of Al88Y8−xFe4+x (x = 0, 1, 2 at.%) Alloys

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1581
Author(s):  
Rafał Babilas ◽  
Monika Spilka ◽  
Katarzyna Młynarek ◽  
Wojciech Łoński ◽  
Dariusz Łukowiec ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Analytical Techniques ◽  
Corrosion Current ◽  
Glass Forming Ability ◽  
Electrochemical Tests ◽  
Glass Forming ◽  
Transmission Electron ◽  
Composition And Structure ◽  
Amorphous Structures ◽  
The Impact

The effect of iron and yttrium additions on glass forming ability and corrosion resistance of Al88Y8-xFe4+x (x = 0, 1, 2 at.%) alloys in the form of ingots and melt-spun ribbons was investigated. The crystalline multiphase structure of ingots and amorphous-crystalline structure of ribbons were examined by a number of analytical techniques including X-ray diffraction, Mössbauer spectroscopy, and transmission electron microscopy. It was confirmed that the higher Fe additions contributed to formation of amorphous structures. The impact of chemical composition and structure of alloys on their corrosion resistance was characterized by electrochemical tests in 3.5% NaCl solution at 25 °C. The identification of the mechanism of chemical reactions taking place during polarization test along with the morphology and internal structure of the surface oxide films generated was performed. It was revealed that the best corrosion resistance was achieved for the Al88Y7Fe5 alloy in the form of ribbon, which exhibited the lowest corrosion current density (jcorr = 0.09 μA/cm2) and the highest polarization resistance (Rp = 96.7 kΩ∙cm2).

Experimental investigation of electrodeposited Ni-Al2O3/ZrO2 nano composite on HSLA ASTM A860 alloy

2021 ◽  
Author(s):  
Chandrasekhara Sastry Chebiyyam ◽  
Pradeep N ◽  
Shaik AM ◽  
Hafeezur Rahman A ◽  
Sandeep Patil
Keyword(s):  
Grain Size ◽  
Corrosion Resistance ◽  
Composite Coating ◽  
Base Alloy ◽  
Composite Coatings ◽  
Nano Particles ◽  
Alloy Sample ◽  
Nano Composite ◽  
Nano Coating ◽  
Nano Composite Coating

Abstract Nano composite coatings on HSLA ASTM A860 alloy, adds to the barrier efficacy by increase in the microhardness, wear and corrosion resistance of the substrate material. Additionally, reduction of delamination of the nano composite coating sample is ascertained. Ball milling is availed to curtail the coating samples (Al2O3/ZrO2) to nano size, for forming a electrodeposited product on the substrate layer. The curtailment in grain size was ascertained to be 17.62% in Ni-Al2O3/ZrO2 nano composite coating. During the deposition process, due to the presence of Al2O3/ZrO2 nano particles an increase in cathode efficiency is ascertained. An XRD analysis of the nano composite coating indicates a curtailment in grain size along with increase in the nucleation sites causing a surge in the growth of nano coating layer. In correlation to uncoated HSLA ASTM A36 alloy sample, a surge in compressive residual stress by 47.14%, reduction of waviness by 32.14% (AFM analysis), upsurge in microhardness by 67.77% is ascertained in Ni-Al2O3/ZrO2 nano composite coating. Furthermore, in nano coated Ni-Al2O3/ZrO2 composite a reduction is observed pertaining to weight loss and friction coefficients by 27.44% and 13% in correlation to plain uncoated alloy respectively. A morphology analysis after nano coating indicates, Ni-Al2O3/ZrO2 particles occupy the areas of micro holes, reducing the wide gaps and crevice points inside the matrix of the substrate, enacting as a physical barrier to upsurge the corrosion resistance by 67.72% in correlation to HSLA ASTM A860 base alloy.

scholarly journals Microstructural and Corrosion Behavior of High Velocity Arc Sprayed FeCrAl/Al Composite Coating on Q235 Steel Substrate

Coatings ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 542 ◽  
Author(s):  
Ndumia Joseph Ndiithi ◽  
Min Kang ◽  
Jiping Zhu ◽  
Jinran Lin ◽  
Samuel Mbugua Nyambura ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Composite Coating ◽  
High Velocity ◽  
Steel Substrate ◽  
Arc Spraying ◽  
Spray Parameters ◽  
Q235 Steel ◽  
Electrochemical Tests ◽  
Al Composite ◽  
Al Coating

High velocity arc spraying was used to prepare FeCrAl/Al composite coating on Q235 steel substrate by simultaneously spraying FeCrAl wire as the anode and Al wire as the cathode. The composite coating was sprayed with varying voltage and current to obtain optimum coating characteristics. FeCrAl coating was also prepared for comparison purposes. The surface microstructure of the coatings was characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The average microhardness of the coatings and the substrate was analyzed and compared. Corrosion resistance was investigated by means of electrochemical tests. The image results showed that a lamellar structure consisted of interwoven layers of FeCrAl and Al. Al and FeCr constituted the main phases with traces of oxides and AlFe intermetallic compounds. The average porosity was reduced and microhardness of the coatings was improved with increasing voltage and current. The FeCrAl/Al coating formed alternating layers of hard and ductile phases; the corrosion resistance of the coatings in the sodium chloride (NaCl) solution depended on the increase in Al content and spray parameters. The corrosion resistance tests indicated that FeCrAl/Al coating had a better corrosion resistance than the FeCrAl coating. FeCrAl/Al can be used to coat steel substrates and increase their corrosion resistance.

scholarly journals Thickness and corrosion resistance optimization of Micro-ARC oxidation coating on Mg-Al-Li-Zn alloy using Taguchi approach

2020 ◽  
pp. 62-66
Author(s):  
Do Le Hung Toan, Shuo-Jen Lee Do
Keyword(s):  
Corrosion Resistance ◽  
Processing Time ◽  
Electrical Potential ◽  
Surface Protection ◽  
Alkaline Electrolytes ◽  
Micro Arc Oxidation ◽  
Corrosive Environments ◽  
Zn Alloy ◽  
Main Factor

Micro arc oxidation method has been developed in the field of surface protection of magnesium alloys and considered as a simple, highly effective, commercial and environmentally friendly method in industry. MAO coatings are fabricated on novel Mg-Al-Li-Zn alloy to improve the anti-corrosion performance of surface by using friendly alkaline electrolytes under a high electrical potential. The Taguchi method and optimal analysis are used to identify the effects of the three factors including current density, processing time and electrical frequency on coating’s characteristics. The results have shown that the main factor that affects coating thickness and corrosion resistance of coating is the processing time. The results obtained by optimal conditions are consistent with prediction values of Taguchi analysis. The thickness of the coating can help to improve the long-term corrosion protection of a MAO coating in corrosive environments.

scholarly journals Microstructure, friction and corrosion resistance properties of a Ni–Co–Al2O3 composite coating

RSC Advances ◽  
2018 ◽  
Vol 8 (22) ◽  
pp. 12138-12145 ◽  
Author(s):  
Zong-wei Jia ◽  
Wan-chang Sun ◽  
Fang Guo ◽  
Ya-ru Dong ◽  
Xiao-jia Liu
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Composite Coating ◽  
Composite Coatings ◽  
Al2o3 Composite ◽  
Pulsed Electrodeposition

Ni–Co–Al2O3 composite coatings were prepared by pulsed electrodeposition and electrophoresis–electrodeposition on aluminum alloy.

Effect of Corrosive Medium on the Corrosion Resistance of FeCrMoCB Amorphous Alloy Coating

2011 ◽  
Vol 291-294 ◽  
pp. 65-71 ◽  
Author(s):  
Qing Jun Chen ◽  
Lin Li Hu ◽  
Xian Liang Zhou ◽  
Xiao Zhen Hua ◽  
Ying Jun Yang
Keyword(s):  
Corrosion Resistance ◽  
Amorphous Alloy ◽  
Amorphous Alloys ◽  
Room Temperature ◽  
Electrochemical Impedance ◽  
Equivalent Circuit Model ◽  
Alloy Coating ◽  
Potentiodynamic Polarization Curves ◽  
Naoh Solution ◽  
Oxygen Fuel

The purpose of this study is to investigate the electrochemical properties of Fe44Cr16Mo16C18B6amorphous alloy coating fabricated using high velocity oxygen fuel (HVOF) technology in 2.0M HCl and NaOH solution at room temperature(25°C). Based on the potentiodynamic polarization curves and Electrochemical Impedance Spectroscopy(EIS) testing results of coating in aqueous solutions of HCl and NaOH, the corrosion resistance of Fe44Cr16Mo16C18B6amorphous alloy coating in HCl solution was superior to that in NaOH solution. The icorrwas 1.487×10-5A·cm-2in HClsolution and 1.107×10-4A·cm-2in NaOH solution, while the Rtreach to 5.789×104Ω·cm2and 9780Ω·cm2, respectively. On the other hand, these corrosion phenomenon could be better interpreted by R(Q(R(RQW)))(RL) and R(RL)(Q(R(CW))) equivalent circuit model, which were different from that of other Fe-based amorphous alloys in HCl and NaOH solution, respectively.

scholarly journals Composite Coatings of Chromium and Nanodiamond Particles on Steel

2017 ◽  
Vol 62 (4) ◽  
pp. 2421-2424 ◽  
Author(s):  
N. Gidikova ◽  
M. Sulowski ◽  
V. Petkov ◽  
R. Valov ◽  
G. Cempura
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Composite Coating ◽  
Composite Coatings ◽  
Machine Building ◽  
Chromium Coating ◽  
Detonation Synthesis ◽  
Micro Structure ◽  
X Ray ◽  
Average Size

AbstractChrome plating is used to improve the properties of metal surfaces like hardness, corrosion resistance and wear resistance in machine building. To further improve these properties, an electrodeposited chromium coating on steel, modified with nanodiamond particles is proposed. The nanodiamond particles (average size 4 nm measured by TEM) are produced by detonation synthesis (NDDS). The composite coating (Cr+NDDS) has an increased thickness, about two times greater microhardness and finer micro-structure compared to that of unmodified chromium coating obtained under the same galvanization conditions. In the microstructure of specimen obtained from chrome electrolyte with concentration of NDDS 25 g/l or more, “minisections” with chromium shell were found. They were identified by metallographic microscope and X-ray analyser on etched section of chromium plated sample. The object of further research is the dependence of the presence of NDDS in the composite coating from the nanodiamond particles concentration in the chroming electrolyte.

Preparation and Property of Electrodeposited Zn-Fe-SiO2 Composite Coating

2008 ◽  
Vol 373-374 ◽  
pp. 212-215 ◽  
Author(s):  
Yun Ying Fan ◽  
Ying Jie Zhang ◽  
Peng Dong
Keyword(s):  
Corrosion Resistance ◽  
Hydrogen Embrittlement ◽  
Surface Morphology ◽  
Composite Coating ◽  
Hydrogen Content ◽  
Particle Concentration ◽  
Composite Coatings ◽  
Particle Content ◽  
Sulfate Bath ◽  
Sio2 Particles

Electrodeposited Zn and Zn-Fe alloy have been applied widely to protect steel from corrosion, but the property of coating still needs to be improved. In this paper, Zn-Fe-SiO2 composite coatings are electrodeposited from Zn-Fe alloy electrolyte containing SiO2 particles. Zinc based coatings with Fe% >1%(mass) are deposited from sulfate bath, and coatings with Fe% <1%(mass) are deposited from chloride bath. Particle content in the composite coating generally increases with particle concentration under an adequate agitation and then tends to saturation. The optimum particle content in the composite coating is 0.5%(mass). Corrosion resistance, porosity, hydrogen embrittlement and surface morphology of Zn-Fe-SiO2 composite coatings have been tested and compared with electrodeposited Zn and Zn-Fe alloy. The data implies that Zn-Fe-SiO2 composite coating has the best corrosion resistance, lowest porosity, lowest hydrogen content and the finest crystal. All the results show that Zn-Fe-SiO2 composite coating is satisfactory to be used as anti-corrosion material for steel and has a great future in application.

Sign in / Sign up

Export Citation Format

Share Document