Microstructure and Cavitation Erosion Behavior of Carbide-Based Coating Deposited by Electrical Arc Spraying

Two different martensite stainless steel 1Cr17/Carbide-based coatings (C-1 and C-2) were prepared by electrical arc spraying technique. Microstructures of the coatings were investigated by optical microscopy (OM), X-ray diffraction (XRD), scanning election microscopy (SEM). The results show that the C-2 coating has higher hardness and finer structure than the C-1 coating. The cavitation erosion resistance was tested using a China GB6383-86 standard method in fresh water. The cavitation erosion mass loss of the C-2 coating was only 55 percent that of the C-1 coating eroded 15h, the C-2 coating has better cavitation erosion resistance.

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Cavitation Erosion Resistance of Silicified Graphite by Liquid Silicon Penetration Technique

Journal of Tribology ◽

10.1115/1.4035869 ◽

2017 ◽

Vol 139 (6) ◽

Cited By ~ 1

Author(s):

Hongqin Ding ◽

Shuyun Jiang

Keyword(s):

Cavitation Erosion ◽

Erosion Resistance ◽

Test System ◽

Surface Microstructure ◽

Chemical Compositions ◽

X Ray Diffraction ◽

X Ray ◽

Sic Ceramic ◽

Cavitation Erosion Resistance ◽

Sem Morphology

This technical brief studied the cavitation erosion behavior of the silicified graphite. The phase constituents, surface microstructure, and chemical compositions of silicified graphite were examined by using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS), respectively. Cavitation experiments were carried out by using an ultrasonic vibration test system. The experimental results show that the silicified graphite exhibits an excellent cavitation erosion resistance; this can be attributed to the fact that the silicified graphite has the characteristics of both the silicon carbide and the graphite. The SEM morphology studies of the erosion surfaces indicated that the inherent brittleness of SiC ceramic material results in the formation of erosion pits on the surface of silicified graphite.

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Effect of chemical heat treatment on cavitation erosion resistance of stainless steel

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650119845741 ◽

2019 ◽

Vol 233 (11) ◽

pp. 1753-1762

Author(s):

Hongqin Ding ◽

Shuyun Jiang ◽

Jiang Xu

Keyword(s):

Stainless Steel ◽

Mass Loss ◽

Diffusion Layer ◽

Cavitation Erosion ◽

Erosion Resistance ◽

304 Stainless Steel ◽

Chemical Heat ◽

Electrochemical Test ◽

Diffusion Layers ◽

Cavitation Erosion Resistance

The purpose of this paper is to study the effect of chemical heat treatments on cavitation erosion resistance of the 304 stainless steel. Three types of diffusion layers are prepared on the 304 stainless steel using gas nitriding, gas carburizing, and carbonitriding treatments. Phase composition and surface microstructure of the diffusion layers are characterized by X-ray diffraction and scanning electron microscopy. And then, the cavitation erosion behavior of the diffusion layers are tested and compared with the one of the 304 stainless steel. The cavitation test is performed in an ultrasonic vibration system integrated with an electrochemical workstation. The mass loss, scanning electron microscopic morphology, and electrochemical test are adopted to assess the surface damage of the diffusion layers. A measurement for the mechanical properties of the diffusion layers shows that the hardness and the elastic modulus of the gas nitrided diffusion layer, carbonitrided diffusion layer, carburized diffusion layer, and 304 stainless steel are 5.3 GPa and 260 GPa, 4.2 GPa and 236 GPa, 4.0 GPa and 210 GPa, 2.5 GPa and 193 GPa, respectively. A cavitation erosion test of 14 h shows that mass loss of the gas nitrided diffusion layer, carbonitrided diffusion layer, carburized diffusion layer, and 304 stainless steel is 5.19 mg, 8.97 mg, 14.37 mg, and 6.62 mg, respectively. The electrochemical test results also indicate that the gas nitrided diffusion layer has a higher corrosion resistance than the carburized diffusion layer, carbonitrided diffusion layer, and stainless steel under cavitation erosion condition. As a conclusion, the gas nitrided diffusion layer is capable of enhancing the cavitation erosion resistance of the stainless steel, while the carburized diffusion layer and carbonitrided diffusion layer increases the mass loss of the stainless steel under cavitation erosion condition.

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Cavitation Erosion Characteristics of an Iron-Based Coating Prepared by High Velocity Arc Spraying

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.523 ◽

2011 ◽

Vol 189-193 ◽

pp. 523-527

Author(s):

Zhi Hua He ◽

Yu Ping Wu ◽

Hong Bin Sun ◽

Yuan Zheng ◽

Yu Dong ◽

...

Keyword(s):

High Velocity ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Optical Microscope ◽

Arc Spraying ◽

X Ray Diffraction ◽

High Velocity Arc Spraying ◽

Iron Based ◽

And Performance ◽

Cavitation Erosion Resistance

In order to increase cavitation erosion resistance of fluid machinery, an iron-based coating was prepared by high velocity arc spraying (HVAS) on the surface of 1Cr18Ni9Ti stainless steel. The microstructure and performance were investigated respectively by optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), Vickers hardness and vibratory cavitation apparatus. The results indicated that the coating had the higher hardness (8.67GPa) and the finer structure than ZG230-450 (1.86GPa) used actual in water conservancy. Compared with ZG230-450, cavitation erosion resistance of the coating was better, and the coating presented flakiness stripping mode. The results indicated that the HVAS is a promising method to prepare the cavitation resistance coating.

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Cavitation Erosion Resistance and Wear Mechanism Model of Flame-Sprayed Al2O3-40%TiO2/NiMoAl Cermet Coatings

Coatings ◽

10.3390/coatings8070254 ◽

2018 ◽

Vol 8 (7) ◽

pp. 254 ◽

Cited By ~ 19

Author(s):

Mirosław Szala ◽

Tadeusz Hejwowski

Keyword(s):

Cavitation Erosion ◽

Erosion Resistance ◽

Ceramic Powder ◽

X Ray Diffraction ◽

Low Velocity ◽

Cermet Coatings ◽

X Ray ◽

Mechanism Model ◽

Cavitation Erosion Resistance ◽

Sprayed Coatings

This manuscript deals with the cavitation erosion resistance of flame-sprayed Al2O3-40%TiO2/NiMoAl cermet coatings (low-velocity oxy-fuel (LVOF)), a new functional application of cermet coatings. The aim of the study was to investigate the cavitation erosion mechanism and determine the effect of feedstock powder ratio (Al2O3-TiO2/NiMoAl) of LVOF-sprayed cermet coatings on their cavitation erosion resistance. As-sprayed coatings were investigated for roughness, porosity, hardness, and Young’s modulus. Microstructural characteristics of the cross section and the surface of as-sprayed coatings were examined by light optical microscopy (LOM), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) methods. Coating cavitation tests were conducted in accordance with the ASTM G32 standard using an alternative stationary specimen testing method with usage of reference samples made from steel, copper, and aluminum alloys. Cavitation erosion resistance was measured by weight and volume loss, and normalised cavitation erosion resistance was calculated. Surface eroded due to cavitation was examined in successive time intervals by LOM and SEM-EDS. On the basis of coating properties and cavitation investigations, a phenomenological model of the cavitation erosion of Al2O3-40%TiO2/NiMoAl cermet coatings was elaborated. General relationships between their properties, microstructure, and cavitation wear resistance were established. The Al2O3-40%TiO2/NiMoAl composite coating containing 80% ceramic powder has a higher cavitation erosion resistance than the reference aluminium alloy.

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