High Temperature Oxidation Behaviors of Ni-Cr Based Thermal Sprayed Coatings

Ni-Cr coating and Ni-Cr/ZrO2 gradated coating were deposited on C45 carbon steel by high velocity arc spraying and micro-plasma spraying to solve the high temperature oxidation problem of medium carbon steel components. The oxidations of Ni-Cr coating, Ni-Cr/ZrO2 gradated coating and C45 carbon steel substrate were carried out for up to 108 hours in air atmosphere at 1100°C. The oxidation behaviors were investigated after detailed examinations by thermal gravimetric analysis (TGA), x-ray diffraction (XRD) and scanning electron microscopy (SEM). Ni-Cr coating and Ni-Cr/ZrO2 gradated coating show similar and low dynamics curve near to the logarithms function. Surface observations with SEM and XRD reveal that the oxidizing surface of the C45 carbon steel substrate is mainly a loose spherical structure consisted of mainly Fe2O3 and Fe3O4. The surface structures of Ni-Cr coating and Ni-Cr/ZrO2 gradated coating after 108 hours oxidization are rather denser than that of C45 carbon steel, which can effectively improve the properties of the oxidation resistance of C45 carbon steel substrate.

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High-Temperature Oxidation Resistance of Electroless Ni-P-ZrO2 Composite Coatings

Materials Science Forum ◽

10.4028/www.scientific.net/msf.686.569 ◽

2011 ◽

Vol 686 ◽

pp. 569-573 ◽

Cited By ~ 2

Author(s):

Ming Feng Tan ◽

Wan Chang Sun ◽

Lei Zhang ◽

Quan Zhou ◽

Jin Ding

Keyword(s):

High Temperature ◽

Carbon Steel ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Steel Substrate ◽

Composite Coatings ◽

Low Carbon ◽

Temperature Oxidation ◽

P Matrix ◽

Electroless Ni

Electroless Ni-P coating containing ZrO2particles was successfully co-deposited on low carbon steel substrate. The surface and cross-sectional micrographs of the composite coatings were observed with scanning electron microscopy (SEM). And the chemical composition of the coating was analyzed with energy dispersive spectroscopy (EDS). The oxidation resistance was evaluated by weight gains during high temperature oxidation test. The results showed that the embedded ZrO2particles with irregular shape uniformly distributed in the entire Ni-P matrix, and the coating showed a good adhesion to the substrate. The weight gain curves of Ni-P-ZrO2composite coatings and Ni-P coating at 923K oxidation experiments were in accordance with . The ZrO2particles in Ni-P matrix could significantly enhance the high temperature oxidation resistance of the carbon steel substrate as compared to pure Ni-P coating.

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High Temperature Oxidation Behavior of Arc-sprayed FeCrBAlMo Coating

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2016-0114 ◽

2016 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Xin Zhang ◽

Zehua Wang ◽

Jinran Lin

Keyword(s):

High Temperature ◽

High Temperature Oxidation ◽

Oxidation Behavior ◽

Steel Substrate ◽

Arc Spraying ◽

X Ray Diffraction ◽

Temperature Oxidation ◽

X Ray ◽

High Velocity Arc Spraying ◽

High Temperature Oxidation Behavior

AbstractFeCrBAlMo coating was deposited on an AISI 20 steel substrate by high velocity arc spraying (HVAS). Compared with FeCrBSiMo coating and pristine AISI 20 steel, the microstructure and high temperature oxidation behavior of FeCrBAlMo coating were investigated by optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction. Meanwhile, the bonding strength of the coatings was also measured. The results indicated that both coatings were composed of α(Fe,Cr) and Fe

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Arc-Spraying Composite Coatings on Mild Steel for Long-Term High-Temperature Oxidation Protection

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.2039 ◽

2013 ◽

Vol 690-693 ◽

pp. 2039-2045

Author(s):

Zhong Li Zhang ◽

Qi Shen Wang ◽

Peng Rao Wei ◽

Xue Gong

Keyword(s):

High Temperature ◽

High Temperature Oxidation ◽

Protective Coatings ◽

Steel Substrate ◽

Composite Coatings ◽

Arc Spraying ◽

Al Alloy ◽

Temperature Oxidation ◽

Oxidation Protection

An arc-spraying composite coating system for high-temperature oxidation protection is composed of an inner Fe-Cr-Al alloy layer and an Al-Si alloy outer layer. The high-temperature oxidation behavior of the composite coatings on steel substrate was studied during isothermal exposures in air at 900°C. Experiments show that the coatings on steel substrate are not deteriorated and the substrate is protected well, being exposed to high temperatures up to 900°C. Inter diffusion of alloying elements within the protective coatings occur, while the elements, Cr and Al, are also diffusing to the core of the base metal. As test time proceeds, a large number of chromium oxides are generated in situ within the protective coatings, especially close to the coating/substrate interface. The oxides generated increase the bond strength of the coating to the steel substrate, and together with the surface alumina they provide a long-term effective anti-oxidant protection to steel substrate. The results on titanium sponge production site show that the protective coatings on the reactor have provided an effective protection and prolong the lifetime at least forty percent for the reactors.

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Microstructure and High Temperature Oxidation of the Hot-Dipping Al-Si Coating on Low Carbon Steel in Ethanol, Water Vapor and Air at 700°C

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.1775 ◽

2009 ◽

Vol 79-82 ◽

pp. 1775-1778 ◽

Cited By ~ 5

Author(s):

Mohammad Badaruddin ◽

Chaur Jeng Wang

Keyword(s):

Water Vapor ◽

High Temperature ◽

Carbon Steel ◽

High Temperature Oxidation ◽

Steel Substrate ◽

Low Carbon Steel ◽

Composition Gradient ◽

Low Carbon ◽

Temperature Oxidation ◽

Aluminide Layer

Low carbon steel was coated by hot-dipping into a molten Al-10%Si bath. The high-temperature oxidation was performed at 700oC for 1 h to 49 h in air, air +100% H2O, and air + 30% ethanol under atmospheric pressure. An elemental composition distribution, morphologies of the aluminide layer and the oxide scale were characterized by OM, XRD, and SEM/EDS. After hot-dipping treatment, the coating layers consisted of Al, Si, FeAl3, τ5-Fe2Al8Si, and Fe2Al5. The results of high temperature oxidation tests showed the oxidation rate were parabolic law in three different atmospheres. The polyhedral τ1-(Al,Si)5Fe3 formed at a short time oxidation completely transformed to FeAl2 and FeAl due to the composition gradient and the chemical diffusion. The effect of water vapor on the oxidation resistance of the Al-Si coating may be attributed to increase in Al and Fe ions transport, leading to loss of protective aluminide layer by formation of iron oxide nodules on the coating surface and at interface between aluminide layer and the steel substrate.

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Microstructure and Properties of Thermal Sprayed ZrO2-NiCr Coatings

Materials Science Forum ◽

10.4028/www.scientific.net/msf.809-810.546 ◽

2014 ◽

Vol 809-810 ◽

pp. 546-549

Author(s):

Gu Liu ◽

Liu Ying Wang ◽

Wei Wang ◽

Yong Fa Wu

Keyword(s):

Carbon Steel ◽

Thermal Shock ◽

Bonding Strength ◽

Cold Water ◽

Steel Substrate ◽

Composite Coatings ◽

Arc Spraying ◽

Gravimetric Analysis ◽

Temperature Oxidation ◽

Air Atmosphere

NiCr/ZrO2gradated coatings were obtained on C45 carbon steel by high velocity arc spraying and micro-plasma spraying to improve the mechanical and thermal behaviors of the carbon steel. Scanning electronic microscope (SEM) and X-ray diffraction (XRD) were employed to characterize the microstructure of the prepared composite coatings. Mechanical properties including hardness and bonding strength were also evaluated by microhardness tester and electron tensile tester. The thermal shock behaviors were investigated by quenching the coating samples in cold water from 900 °C and 1100 °C, respectively. The oxidation of NiCr/ZrO2gradated coating and C45 carbon steel substrate were carried out for up to 108 hours in air atmosphere at 1100°C. The oxidation behaviors were investigated after detailed examinations by thermal gravimetric analysis. Experimental results indicate that NiCr/ZrO2gradated coating exhibit a much higher hardness and high temperature oxidation behavior than the substrate. The bonding strength and thermal shock behavior of NiCr/ZrO2are superior to pure ZrO2coating, which could be mainly attributed to the NiCr intermediate graded layer due to the microstructure improvement and relaxation of residual stress concentration.

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Increasing Hardness and Corrosion Resistance of Medium-Carbon Steel Surface by Cathodic Plasma Electrolytic Nitriding

Elektronnaya Obrabotka Materialov ◽

10.52577/eom.2021.57.5.27 ◽

2021 ◽

Vol 57 (5) ◽

pp. 27-33

Author(s):

S.A. Kusmanov ◽

◽

I.V., Tambovsky ◽

S.S. Korableva ◽

S.A. Silkin ◽

...

Keyword(s):

High Temperature ◽

Carbon Steel ◽

High Temperature Oxidation ◽

Steel Surface ◽

Medium Carbon Steel ◽

Surface Erosion ◽

Temperature Oxidation ◽

Medium Carbon ◽

Cathodic Plasma ◽

Plasma Electrolytic

The structural-phase composition and some properties of medium-carbon steel modified surface after cathodic plasma electrolytic nitriding in a solution of ammonium chloride and ammonia have been studied. It is shown that cathodic nitriding of a steel surface is accompanied by high-temperature oxidation with the formation of oxides FeO, Fe2O3, and Fe3O4, as well as nitrogen diffusion and quenching with the formation of FeN, Fe3N, and Fe4N phases, martensite and the retained austenite. The competing effect of surface erosion by the actions of discharges and high-temperature oxidation on the morphology and roughness of the surface was revealed. It was established that the maximum microhardness of the modified layer reaches 1040 HV, and the corrosion current density of the nitrided surface decreases by a factor of 1.5–2.4.

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