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Article
Publication date: 3 February 2020

Santosh Kumar, Manoj Kumar and Neeru Jindal

This paper aims to consolidate the results of various researchers focusing the different applications, so that this paper could become the torch bearer for the futuristic…

Abstract

Purpose

This paper aims to consolidate the results of various researchers focusing the different applications, so that this paper could become the torch bearer for the futuristic researchers working in the domain of cold gas dynamics spray coating.

Design/methodology/approach

A study on the cold spray coating is presented by summarizing the data present in literature. Important factors such as coating temperature, pressure, coating thickness, particle size, which affect the erosion-corrosion (E-C) resistance, physical and mechanical properties of boiler steel are stated. This paper also addresses the use of cold spray coating and compares it with other different thermal spray processes.

Findings

From the literature review, it was noticed that cold spray technology is best as compare to other thermal spray processes to reduce porosity, increase hardness, adhesion strength and retention in properties of feedstock powders.

Originality/value

Cold spray coating technology has a great potential in almost every field especially in restoration of surfaces, generation of complex surface, biomedical application, resist hot corrosion, wear, oxidation and erosion corrosion.

Details

World Journal of Engineering, vol. 17 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 17 September 2021

Wang Zhizhong, Han Chao, Guosheng Huang, Han Bin and Han Bin

The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient…

Abstract

Purpose

The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.

Design/methodology/approach

This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.

Findings

There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.

Originality/value

It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.

Details

Rapid Prototyping Journal, vol. 28 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 27 September 2018

Zhang Jing and Kong Dejun

To improve the electrochemical corrosion resistance of cold sprayed Al coating.

Abstract

Purpose

To improve the electrochemical corrosion resistance of cold sprayed Al coating.

Design/methodology/approach

A cold sprayed aluminum (Al) coating fabricated on S355 structural steel was oxidized using a micro arc oxidation (MAO). The electrochemical corrosion and impedance spectroscopy were tested to investigate its corrosion performance.

Findings

The MAO film is primarily α-Al2O3 and γ-Al2O3, which increases its density and surface quality. The corrosion potential is positively shifted by 0.2 V, and the electrochemical impedance is significantly increased.

Originality/value

A cold sprayed Al coating on S355 steel was first oxidized using a MAO. The effects of MAO on the microstructure of Al coating were investigated to analyze its electrochemical corrosion behavior.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 8 July 2019

Jashanpreet Singh

The purpose of this study is to analyze the slurry erosion failure of Ni-20Cr (Ni-Cr2O3), Ni-20Al (Ni-Al2O3) and Al-20Ti (Al2O3-TiO2) coatings deposited on SS316L by the…

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Abstract

Purpose

The purpose of this study is to analyze the slurry erosion failure of Ni-20Cr (Ni-Cr2O3), Ni-20Al (Ni-Al2O3) and Al-20Ti (Al2O3-TiO2) coatings deposited on SS316L by the high-velocity oxy-fuel process.

Design/methodology/approach

Slurry erosion experiments were conducted using a pot type erosion tester at different velocities 1.81, 2.71, 3.61 and 4.59 m/s for the time duration of 90-180 minutes. Fly ash and bottom ash were used as erodent media; the concentration of mass flux was taken as 30-60 wt. per cent. Artificial neural network (ANN) method was used to simulate the slurry erosion for thermally sprayed coatings.

Findings

Slurry erosion of coatings increases non-linearly with an increase in experimental durations, mass flux and velocity. Slurry erosion of Ni-20Cr and Ni-20Al layers was found to be maximum at 60° impingement angle, whereas 30° for SS316L and 45° for Al-20Ti coating. Slurry erosion performance of SS316L was improved by 2.56-3.19 times by depositing Ni-20Cr and Ni-20Al layers, whereas it improved 1.15-1.75 times by Al-20Ti coating. The slurry erosion SS316L was found almost 1.35 ± 1.28 times greater than that of the Ni-20Al coating, whereas it was to be 1.12 ± 1.36 times greater than Al-20Ti. Ni-20Al-coated SS316L showed a lower value of slurry erosion than Al-20Ti-coated SS316L.

Practical implications

Stainless Steel SS316L is widely used in hydraulic machinery (such as turbines, pumps, valves, fittings, etc.) of hydraulic and thermal power plants, chemical industry and marine industry. Therefore, the deposition of ductile and brittle coatings is a better option for their durable performance.

Originality/value

Erosion wear of Ni-20Cr, Ni-20Al and Al-20Ti coatings was successfully simulated by using an artificial neural network model by supplying experimental data as a target.

Details

Industrial Lubrication and Tribology, vol. 71 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 7 November 2016

Guosheng Huang, Xiangbo Li and Lukuo Xing

This paper aims to examine the performance of low-pressure cold-sprayed zinc–nickel (Zn-Ni) composites coating, i.e. whether it has the same performance as Zn-Ni alloy coating.

Abstract

Purpose

This paper aims to examine the performance of low-pressure cold-sprayed zinc–nickel (Zn-Ni) composites coating, i.e. whether it has the same performance as Zn-Ni alloy coating.

Design/methodology/approach

In this paper, Zn-Ni composites coatings containing four different nickel contents were prepared with commercial DYMET 413 low-pressure cold spraying system under the same parameters. Corrosion behaviors of four kinds of coatings were examined with potentiodynamic polarization curves and electrochemical impedance spectroscopy methods, combined with scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction.

Findings

Corrosion behavior of Zn-Ni composites coating is similar to Zn-Ni alloy coating. In the early stages of immersion, the anodic dissolution of zinc happens, which results in the formation of a zinc hydroxide layer. With the continuous infiltration of chloride ion, zinc hydroxide will get converted to zinc oxide, basic zinc chloride and basic zinc carbonate. The presence of nickel in coatings can prevent zinc hydroxide from converting into zinc oxide.

Research limitations/implications

Further research should be done on improving the deposition efficiency, as the deposition efficiency of low-pressure cold spray is lower than 30 per cent.

Practical implications

Low-pressure cold spray coating can be used in cyclic dry/wet conditions to prolong the life of a steel structure.

Social implications

Low-pressure cold spray Zn-Ni coating is an environmentally friendly anticorrosion method which can be used as an alternative of hexavalent chromium passivation coating.

Originality/value

Zn-Ni composite coating can be deposited on steel directly by low-pressure cold spray by mechanically mixing the powders together. The composite coating also has the same long-term anticorrosion performance as Zn-Ni alloy coating.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 2 August 2019

Guosheng Huang, Wei Fu, Juan Zhou, Li Ma, Hongren Wang and Xiangbo Li

The purpose of this paper is to examine the performance of cold-sprayed Zn15Al alloy coating whether it is capable of protecting magnesium alloy from corrosion, and to compare it…

Abstract

Purpose

The purpose of this paper is to examine the performance of cold-sprayed Zn15Al alloy coating whether it is capable of protecting magnesium alloy from corrosion, and to compare it with arc-sprayed Zn15Al alloy coating.

Design/methodology/approach

In this paper, Zn15Al alloy coating was prepared with CS-6000 cold spraying system and HDX-800 arc-sprayed system. Corrosion behaviors of the two kinds of coatings were examined with potentiodynamic polarization curves methods combined with SEM, EDS, XRD, etc.

Findings

Corrosion behavior of cold-sprayed Zn15Al alloy coating is superior to arc-sprayed Zn15Al alloy coating. The bonding strength and density of cold-sprayed Zn15Al alloy coating is much higher than that of arc-sprayed Zn15Al alloy coating. The cold-sprayed coating has a dense structure which separate magnesium from corrosion medium completely. The samples behave as Zn15Al instead of AZ91D alloy. The coating has a low probability of pitting corrosion comparing with cold sprayed Al coating through potentiodynamic polarization curve.

Practical implications

Cold-sprayed Zn15Al coating can be used to improve the anticorrosion performance of magnesium significantly and low down the risk of pitting corrosion of coating.

Social implications

Cold-sprayed Zn15Al coating is an environmentally friendly anticorrosion method for light alloy, which is also the most effective way among thermal spray, chemical vapor deposition, sol–gel, plating and anodizing or microarc oxidation.

Originality/value

The present paper used cold spray method to deposit Zn15Al coating, which has an overwhelming performance both in physical and anticorrosion to traditional thermal spray method.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 6 November 2020

Alain Fossi, Alain DeChamplain, Benjamin Akih-Kumgeh and Jeffrey Bergthorson

This study aims to deal with the large eddy simulation (LES) of an ignition sequence and the resulting steady combustion in a swirl-stabilized liquid-fueled combustor. Particular…

Abstract

Purpose

This study aims to deal with the large eddy simulation (LES) of an ignition sequence and the resulting steady combustion in a swirl-stabilized liquid-fueled combustor. Particular attention is paid to the ease of handling the numerical tool, the accuracy of the results and the reasonable computational cost involved. The primary aim of the study is to appraise the ability of the newly developed computational fluid dynamics (CFD) methodology to retrieve the spark-based flame kernel initiation, its propagation until the full ignition of the combustion chamber, the flame stabilization and the combustion processes governing the steady combustion regime.

Design/methodology/approach

The CFD model consists of an LES-based spray module coupled to a subgrid-scale ignition model to capture the flame kernel initiation and the early stage of the flame kernel growth, and a combustion model based on the mixture fraction-progress variable formulation in the line of the flamelet generated manifold (FGM) method to retrieve the subsequent flame propagation and combustion properties. The LES-spray module is based on an Eulerian-Lagrangian approach and includes a fully two-way coupling at each time step to account for the interactions between the liquid and the gaseous phases. The Wall-Adapting Local Eddy-viscosity (WALE) model is used for the flow field while the eddy diffusivity model is used for the scalar fluxes. The fuel is liquid kerosene, injected in the form of a polydisperse spray of droplets. The spray dynamics are tracked using the Lagrangian procedure, and the phase transition of droplets is calculated using a non-equilibrium evaporation model. The oxidation mechanism of the Jet A-1 surrogate is described through a reduced reaction mechanism derived from a detailed mechanism using a species sensitivity method.

Findings

By comparing the numerical results with a set of published data for a swirl-stabilized spray flame, the proposed CFD methodology is found capable of capturing the whole spark-based ignition sequence in a liquid-fueled combustion chamber and the main flame characteristics in the steady combustion regime with reasonable computing costs.

Research limitations/implications

The proposed CFD methodology simulates the whole ignition sequence, namely, the flame kernel initiation, its propagation to fully ignite the combustion chamber, and the global flame stabilization. Due to the lack of experimental ignition data on this liquid-fueled configuration, the ability of the proposed CFD methodology to accurately predict ignition timing was not quantitatively assessed. It would, therefore, be interesting to apply this CFD methodology to other configurations that have experimental ignition data, to quantitatively assess its ability to predict the ignition timing and the flame characteristics during the ignition sequence. Such further investigations will not only provide further validation of the proposed methodology but also will potentially identify its shortfalls for better improvement.

Practical implications

This CFD methodology is developed by customizing a commercial CFD code widely used in the industry. It is, therefore, directly applicable to practical configurations, and provides not only a relatively straightforward approach to predict an ignition sequence in liquid-fueled combustion chambers but also a robust way to predict the flame characteristics in the steady combustion regime as significant improvements are noticed on the prediction of slow species.

Originality/value

The incorporation of the subgrid ignition model paired with a combustion model based on tabulated chemistry allows reducing computational costs involved in the simulation of the ignition phase. The incorporation of the FGM-based tabulated chemistry provides a drastic reduction of computing resources with reasonable accuracy. The CFD methodology is developed using the platform of a commercial CFD code widely used in the industry for relatively straightforward applicability.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 3 April 2019

Dibakor Boruah, Xiang Zhang and Matthew Doré

The purpose of this paper is to develop a simple analytical model for predicting the through-thickness distribution of residual stresses in a cold spray (CS) deposit-substrate…

Abstract

Purpose

The purpose of this paper is to develop a simple analytical model for predicting the through-thickness distribution of residual stresses in a cold spray (CS) deposit-substrate assembly.

Design/methodology/approach

Layer-by-layer build-up of residual stresses induced by both the peening dominant and thermal mismatch dominant CS processes, taking into account the force and moment equilibrium requirements. The proposed model has been validated with the neutron diffraction measurements, taken from the published literature for different combinations of deposit-substrate assemblies comprising Cu, Mg, Ti, Al and Al alloys.

Findings

Through a parametric study, the influence of geometrical variables (number of layers, substrate height and individual layer height) on the through-thickness residual stress distribution and magnitude are elucidated. Both the number of deposited layers and substrate height affect residual stress magnitude, whereas the individual layer height has little effect. A good agreement has been achieved between the experimentally measured stress distributions and predictions by the proposed model.

Originality/value

The proposed model provides a more thorough explanation of residual stress development mechanisms by the CS process along with mathematical representation. Comparing to existing analytical and finite element methods, it provides a quicker estimation of the residual stress distribution and magnitude. This paper provides comparisons and contrast of the two different residual stress mechanisms: the peening dominant and the thermal mismatch dominant. The proposed model allows parametric studies of geometric variables, and can potentially contribute to CS process optimisation aiming at residual stress control.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 26 July 2019

Yasin Ozgurluk, Kadir Mert Doleker and Abdullah Cahit Karaoglanli

Thermal barrier coatings (TBCs), which are used in high temperature applications of gas turbines, are damaged due to fuels and airborne minerals under working conditions. Stable…

Abstract

Purpose

Thermal barrier coatings (TBCs), which are used in high temperature applications of gas turbines, are damaged due to fuels and airborne minerals under working conditions. Stable zirconia coatings, which are usually used as topcoat materials in TBCs, are damaged by interacting at high temperatures with elements such as vanadium and sulfur from low quality fuels. The purpose of this paper is to see the failure mechanism of TBC systems after hot corrosion damages.

Design/methodology/approach

CoNiCrAlY metallic bond coatings of TBC samples were produced by cold gas dynamic spray method which is a new trend production method and stabilized zirconia ceramic top coating was produced by atmospheric plasma spray method. In total, 50% by weight of V2O5 and 50% Na2SO4 salt mixtures were placed on TBC samples and subjected to hot corrosion test at 1000°C.

Findings

Hot corrosion behaviors of TBC samples were examined by scanning electron microscopy, elemental mapping analysis, energy dispersive X-ray spectrometry analysis and X-ray diffraction analysis. TBC samples were damaged at the end of 12-h cycles.

Originality/value

The paper provides to understand the mechanism of hot corrosion of TBCs with cold sprayed metallic bond coat.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 13 March 2017

Cagdas Calli, Onur Tazegul and Eyup Sabri Kayali

The purpose of this paper is to investigate the effects of reinforcing particles (B4C, TiB2 and TiC) on the physical, corrosion and wear behaviour of copper matrix composite…

Abstract

Purpose

The purpose of this paper is to investigate the effects of reinforcing particles (B4C, TiB2 and TiC) on the physical, corrosion and wear behaviour of copper matrix composite coatings.

Design/methodology/approach

Coatings were produced by cold gas dynamic spraying process, and the contribution of reinforcements (B4C, TiB2 and TiC) to the coating characteristics was detected through microstructural examinations (scanning electron microscope examinations and X-ray diffraction analyses), hardness and electrical conductivity measurements, corrosion tests in Cl environment with potentiostat/galvonostat apparatus and wear tests which were performed under dry conditions by reciprocating wear tester.

Findings

Coatings with high density, good bonding at the coating and substrate interface were obtained by cold gas dynamic spray process. The electrochemical polarisation test in a Cl environment clearly indicated that the type of reinforcing particles did not significantly affect the corrosion performances of pure copper coating. In terms of the wear performances of the coatings, the best wear performance has been obtained for pure copper coating. Wear performance reduction of the composite coatings was related to the inhibition of continuous oxide layer formation on the worn surfaces due to third-body abrasion mechanism and delamination of oxide layer during wear tests.

Originality/value

Contrary to expectations, wear tests results of the study revealed the inverse effect of ceramic particle addition to the copper matrix in cold spray coating applications due to poor bonding between matrix and reinforcing particles.

Details

Industrial Lubrication and Tribology, vol. 69 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

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