Neural network analysis for erosive wear of hard coatings deposited by thermal spray: Influence of microstructure and mechanical properties (original) (raw)
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Metallurgical and Materials Transactions A, 2017
An evaluation of the relationship between the microhardness and fracture toughness with resistance to erosive wear of WC10Co4Cr, WC-12Co, and Cr3C2-25NiCr coatings was conducted. Powder and flexible cored wire feedstock materials were applied by high-velocity oxygen fuel (HVOF) and flame spray (FS), respectively. The erosive wear mechanism prevailing in the coatings was found to be brittle, which also explains the higher erosion rate for the experimental condition using the particle impact angle of 90 deg and impact velocity of 9.33 m/ s. The best wear performance was for the coatings applied by HVOF that attains 1.83 mm 3 /kg for the 90 deg/3.61 m/s test condition. The coating obtained with the WC-10Co4Cr material using the FSFC method showed tungsten carbide decarburization, justifying its poor mechanical properties and poor performance in the erosive wear test. Flame-sprayed flexicords proved to be a promising alternative to HVOF in obtaining coatings with low porosity and acceptable mechanical properties, especially in applications where the use of the HVOF technique is inadequate because of inaccessibility or excessively high cost. Values of K c for the coatings obtained by HVOF (7.35 to 10.83 MPa.m 1/2) were between two and three times greater than the values obtained for the coatings resulting from FSFC (2.39 to 3.59 MPa.m 1/2), in a similar manner as with the microhardness.
The wear resistance of thermal spray the tungsten and chromium carbides coatings
Journal of achievements in materials and manufacturing engineering, 2011
Purpose: The objective of the work concerns of wear-resistance of different kinds of thermal spray coatings covering industrial fun blades. The coatings were sprayed onto the fun blades by Plasma Spraying and High Velocity Oxygen Fuel Spraying (HVOF) methods. The Cr3C2, WC and also its compositions were sprayed into the fun blades. The coatings were tested in industry conditions and the effect of influence of centrifugation industry emissions on the stage of the wearing after the exploitation was compared for deposited coatings. Design/methodology/approach: The investigations of coating microstructures by optical microscopy (MO) and transmission electron microscopy (TEM) were performed. The examination of fun blades after the exploitation and the analysis of the obtained results was correlated with the performed microstructure observations and microhardness data of coatings. Findings: The microstructures of Cr and W carbides coatings were observed and analyzed. The microhardness of ...
Materials Research Express, 2020
The present study investigated the erosion wear behavior of WC-Ni and WC-Cr3C2-Ni cermet coatings deposited by high velocity oxy-fuel (HVOF) spray process on the substrate of 1Cr18Ni9Ti stainless steel. Microstructures and morphologies of the coatings were examined using SEM images, and x-ray diffractometer was used to analyze the phase composition of the powder and the coatings. The erosion test was carried out using home-made jet rig. In order to better fit the research background of this study, the erodent used for erosion was taken from the Yellow River, China. The coating is well combined with the substrate; and WC-Cr3C2-Ni coating consists of WC, Cr3C2 and Ni phases, WC-Ni coating consists of WC, W2C and Ni phases. Some mechanical properties of the two coatings were compared, WC-Cr3C2-Ni coatings have higher hardness to be compared with WC-Ni ones due to a lower binder content; and the elasticity modulus and nano-hardness values of the WC-Cr3C2-Ni coating are higher than that ...
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Surface and Coatings Technology, 2000
Thermally sprayed WC/Co cermet coatings are widely used for their resistance to abrasive wear. In this work the influence of the abrasive grain size on the abrasive wear resistance was investigated for WC/Co coatings sprayed with several processes: APS, high-velocity oxy-fuel (HVOF ) and VPS. Results show that the larger the abrasive particle size, the lower the abrasion resistance of the coatings. Moreover, among the thermal spray techniques tested, HVOF coatings have the best wear resistance while VPS coatings present the lowest resistance. The role of the coating microstructure and residual stresses on the wear track and morphologies, as well as the abrasive wear behaviour, are discussed.
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Influence of Thermal Spraying Method on the Properties of Tungsten Carbide Coatings
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SSRN Electronic Journal
The thermal spray coatings are commonly employed in slurry pump components and hydrodynamic turbine blades, where wear progression is an intricate phenomenon. In this research work, the performance analysis of HVOF and APS sprayed WC20Cr3C27Ni coatings for slurry erosion wear is carried out by using arti cial neural networks (ANN). The in uence of time, particle size, impact angle, speed, and slurry concentration on wear performance of coatings and turbine steel substrate are evaluated. Under the experimental settings, slurry erosion wear rates and mass loss for both coatings and substrate were determined. When ASTM A743 steel was coated with thermal sprayed WC20Cr3C27Ni coatings, the slurry erosion wear resistance of the steel was enhanced by 2 and 3.5 times for APS and HVOF coatings, respectively. The design of ANN made it possible to examine the interactions between the seven input variables. A robust model was formed by the two outputs that followed. This model enables the prediction of slurry erosion wear rate and mass loss of WC20Cr3C27Ni coatings and substrate.
IJERT-Wear Behaviour of Cermet Coatings Deposited by Different Thermal Spray Techniques: A Review
International Journal of Engineering Research and Technology (IJERT), 2016
https://www.ijert.org/wear-behaviour-of-cermet-coatings-deposited-by-different-thermal-spray-techniques-a-review https://www.ijert.org/research/wear-behaviour-of-cermet-coatings-deposited-by-different-thermal-spray-techniques-a-review-IJERTV5IS030846.pdf Wear and erosion are recognized as a serious problems in coal based power plants, hydro power plants, turbine blades, aircrafts, piston-cylinder mechanism, penstocks and in various industry components. This results the premature failure of the working component or these component does not perform its function properly so there are essential requirement to alter or repair it and one of best option to overcome this problem is the use of protective coatings either nanostructured or conventional coatings. Different composition of WC/Cr3C2NiCr coatings are used to enhance the erosion and wear resistance of component in industries. The Nano coatings have good hardness, highly dense, very low porosity and excellent wear resistance so it has great competence to resists the spallation, wear and erosion. In this review paper analysis of previous literatures and summarised the effect of wear and erosion, erodent size and shape, different coating material compositions and thermal spray process and the properties of erosion and wear on the substrate.
Solid Particle Erosion Performance of Multilayered Carbide Coatings (WC-SiC-Cr_3C_2
Transdisciplinary Research and Education Center for Green Technologies, Kyushu University, 2023
A modern machine parts such as gas turbine blades and vanes are impacted by high temperature and high speed solid dust particles. As a result may leads to disastrous failure. In order to increase the performance multilayered (WC-SiC-Cr3C2) carbide coating was developed on AISI 304 steel using HVOF process. Erosion test as per ASTM G 76 standard were conducted at differently impingement angle (90, 75, 60, 45 and 30)at room temperature. Micro structural, morphological and element analysis probed using SEM and EDAX. The changes in the resistance to erosion are due to high hardness and less porosity of the developed coating. The analysis showed a well-adhered and dense layer with a uniform distribution and presence of carbides and ability to withstand the erosive effects of solid dust particles.
Hydroabrasive wear behaviour of high velocity oxyfuel thermally sprayed WC-M coatings
Surface & Coatings Technology, 1993
Hydroabrasive wear tests were conducted on the coatings of tungsten carbide-metal matrix cermets of type WC-M, where M Co, CoCr and Ni. The coatings were deposited using the high velocity oxyfuel (HVOF) spraying process. Cermets of the cobalt binder phase showed 50%-200% higher strength than those of the nickel matrix depending on the erosion conditions, and the addition of chromium improved the erosion resistance several times. Analytical techniques including X-ray diffraction and energy-dispersive spectroscopy (EDS) as well as transmission electron microscopy were used to characterize microstructures formed during powder processing and spraying. Owing to overheating of powder particles within the spray torch, the HVOF cermets develop complex microstructures. The hard phase consists basically of tungsten monocarbide (WC) as well as ditungsten carbide (W 2C), while the binder phase obtains a nanocrystalline structure of the size between 4 and 8 nm, containing ternary carbides and mixed compounds. The erosion results are discussed with respect to the microstructural features developed during spraying.