A Study on Corrosion and Corrosion-Wear Behavior of Fe-based Amorphous Alloy Coating Prepared by High Velocity Oxygen Fuel Method

In this study, Fe40Cr19Mo18C15B8 amorphous coatings were prepared using high velocity oxygen fuel (HVOF) technology. Different temperatures were used in the heat treatment (600 °C, 650 °C, and 700 °C) and the annealed coatings were analyzed by DSC, SEM, TEM, and XRD. XRD and DSC results showed that the coating started to form a crystalline structure after annealing at 650 °C. From the SEM observation, it can be found that when the annealing temperature of the Fe-based amorphous alloy coating reached 700 °C, the surface morphology of the coating became relatively flat. TEM observation showed that when the annealing temperature of the Fe-based amorphous alloy coating was 700 °C, crystal grains in the coating recrystallized with a grain size of 5–20 nm. SAED analysis showed that the precipitated carbide phase was M23C6 phase with different crystal orientations (M = Fe, Cr, Mo). Finally, the corrosion polarization curve showed that the corrosion current density of the coating after annealing only increased by 9.13 μA/cm2, which indicated that the coating after annealing treatment still had excellent corrosion resistance. It also proved that the Fe-based amorphous alloy coating can be used in high-temperature environments. XPS analysis showed that after annealing FeO and Fe2O3 oxide components increased, and the formation of a large number of crystals in the coating resulted in a decrease in corrosion resistance.

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Comparative analysis of tribological behavior of plasma- and high-velocity oxygen fuel-sprayed WC-10Co-4Cr coatings

Industrial Lubrication and Tribology ◽

10.1108/ilt-09-2015-0129 ◽

2017 ◽

Vol 69 (2) ◽

pp. 325-332 ◽

Cited By ~ 3

Author(s):

Shiyu Cui ◽

Qiang Miao ◽

Wenping Liang ◽

Yi Xu ◽

Baiqiang Li

Keyword(s):

Plasma Spraying ◽

High Velocity ◽

Wear Mechanisms ◽

Wear Behavior ◽

High Velocity Oxygen Fuel ◽

Hvof Spraying ◽

Content Type ◽

Q235 Steel ◽

Oxygen Fuel ◽

Sprayed Coatings

Purpose The purpose of this study is to prepare WC-10Co-4Cr coatings using two processes of plasma spraying and high-velocity oxygen fuel (HVOF) spraying. The decarburization behaviors of the different processes are analyzed individually. The microstructural characteristics of the as-sprayed coatings are presented and the wear mechanisms of the different WC–10Co–4Cr coatings are discussed in detail. Design/methodology/approach The WC–10Co–4Cr coatings were formed on the surface of Q235 steel by plasma and HVOF spraying. Findings Plasma spraying causes more decarburizing decomposition of the WC phase than HVOF spraying. In the plasma spraying process, η(Cr25Co25W8C2) phase appears and the C content decreases from the top surface of the coating to the substrate. Practical implications In this study, two WC–10Co–4Cr coatings on Q235 steel prepared by plasma and HVOF spraying were compared with respect to the sliding wear behavior. Originality/value The wear mechanisms of the plasma- and HVOF-sprayed coatings were abrasive and oxidation, respectively.

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Optimizing the Substrate Preheating Process of High Velocity Oxygen Fuel Cobalt-Based Alloy Coating on Alloyed and Carbon Steels Mechanical Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.929.142 ◽

2018 ◽

Vol 929 ◽

pp. 142-149 ◽

Cited By ~ 1

Author(s):

Myrna Ariati Mochtar ◽

Wahyuaji Narottama Putra ◽

Raditya Perdana Rachmansyah

Keyword(s):

Wear Resistance ◽

High Velocity ◽

Alloy Coating ◽

Carbon Steels ◽

Surface Heating ◽

Initial Surface ◽

High Velocity Oxygen Fuel ◽

Alternative Material ◽

Substrate Preheating ◽

Oxygen Fuel

Tube boiler operating condition initiates common problems that can occur as a problem in the wear resistance material. It leads to a decreased function of the material so that it is necessary to repair or replacement. High Velocity Oxygen Fuel (HVOF) is regarded as one of the effective methods to increase the wear resistance of the material. In this study, the materials were ASTM SA213-T91 as a material commonly used for boiler tube and JIS G 3132 SPHT-2 as an alternative material. In the early stages, both of specimens were given initial surface heating with temperature variations 0, 50, 100 and 150oC. The materials were then coated with Stellite-1 using HVOF method. The material were then characterized for the microstructure, porosity, hardness distribution, and wear resistant. The results showed that the coating Stellite-1 as a top coat with HVOF method can improve the performance of the material. Microhardness increases from 220 HV to 770 HV on ASTM SA213-T91, while on the substrate JIS G 3132 SPHT-2 the microhardness increased from 120 HV to 750 HV. Better wear resistance was achieved with increasing preheating [1]. Wear resistance of the materials increased from the range 3.69x10-7at 0°C preheating up to 0.89x10-7on a specimen with initial surface heating 150oC. Porosity also decreases with the increasing preheating temperature.

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CORROSION AND WEAR BEHAVIOR OF HIGH VELOCITY OXYGEN FUEL SPRAYED WC-CO COATINGS

SGEM2011 11th International Multidisciplinary Scientific GeoConference ◽

10.5593/sgem2011/s12.104 ◽

2011 ◽

Cited By ~ 1

Author(s):

Dragos Utu

Keyword(s):

High Velocity ◽

Wear Behavior ◽

Corrosion And Wear ◽

High Velocity Oxygen Fuel ◽

Oxygen Fuel

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Numerical Analysis of High-Velocity Oxygen Fuel Thermal-Spray Process for Fe-Based Amorphous Coatings

Coatings ◽

10.3390/coatings11121533 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1533

Author(s):

Jianxing Yu ◽

Xin Liu ◽

Yang Yu ◽

Haoda Li ◽

Pengfei Liu ◽

...

Keyword(s):

Amorphous Alloy ◽

High Velocity ◽

Injection Rate ◽

Amorphous Coating ◽

High Velocity Oxygen Fuel ◽

Alloy Particle ◽

Coating Structure ◽

Particle Behavior ◽

Spray Process ◽

Oxygen Fuel

High-velocity oxygen fuel (HVOF)-sprayed amorphous alloy coatings usually have advantages of a dense structure that improve their resistance to corrosion, wear, and fatigue in the substrate. The flame flow characteristics and particle behaviors during the spray process have a significant influence on the amorphous coating structure and properties. In this study, a computational fluid dynamics model is enforced to analyze the flame flow and Fe-based amorphous alloy particle behavior in an HVOF spray process. The flame flow temperature, velocity characteristics, and the Fe48Cr15Mo14C15B6Y2 Fe-based amorphous alloy particles’ velocities, temperatures, flight trajectories, and mass concentration distribution characteristics are simulated. Moreover, the effects of the oxygen/fuel ratio, particle morphology parameter, particle-injection rate, and angle on the particle behavior are also investigated. Judging from the simulation results, the optimum amorphous alloy particle size varies between 20 and 30 μm, the shape factor is within the range of 0.9–1, the optimum O/F ratio is 3.4, the optimum injection angle is 45°, and the optimum injection rate is 10 m/s. With these conditions, most of the particles settled toward the centerline of the spray gun and are in a semisolid or solid state before affecting the substrate, giving the materials optimal coating structure and performance.

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