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Article
Publication date: 6 February 2009

Rambabu Arji, D.K. Dwivedi and S.R. Gupta

The paper's aim is to investigate the sand slurry erosive wear behaviour of Ni‐Cr‐Si‐B coating deposited on mild steel by flame spraying process under different test conditions.

Abstract

Purpose

The paper's aim is to investigate the sand slurry erosive wear behaviour of Ni‐Cr‐Si‐B coating deposited on mild steel by flame spraying process under different test conditions.

Design/methodology/approach

Flame sprayed coatings of Ni‐Cr‐Si‐B were developed on mild steel substrate The slurry pot tester was used to evaluate wear behaviour of the coating and mild steel. The erosive wear test was conducted using 20 and 40 per cent silica sand slurry at three rotational speeds (600, 800 and 1,000 rpm).

Findings

Slurry erosive wear of the coating showed that in case of 20 per cent silica sand slurry weight loss increases with increase in rotational speed from 600 to 1,000 rpm while in case of 40 per cent silica sand slurry weight loss first increases with increase in rotational speed from 600 to 800 rpm followed by marginal decrease in weight loss with further increase in rotational speed from 800 to 1,000 rpm. Increase in wear resistance due to thermal spray coating of Ni base alloy on mild steel was quantified as wear ratio (weight loss of mild steel and that of coating under identical erosion test conditions). Wear ratio for Ni‐Cr‐Si‐B coating was found in range of 1.4‐2.8 under different test conditions. The microstructure and microhardness study of coating has been reported and attempts have been to discuss wear behaviour in light of microstructure and microhardness. Scanning electron microscope (SEM) study of wear surface showed that loss of material from the coating surface takes place by indentation, crater formation and lip formation and its fracture.

Practical implications

It would assist in estimating the erosion wear performance of flame sprayed Ni‐Cr coatings and their affects of wear resistance.

Originality/value

Erosion wear of flame sprayed coatings in sand slurry media medium is substantiated by extensive SEM study.

Details

Industrial Lubrication and Tribology, vol. 61 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 25 September 2018

Kaushal Kumar, Satish Kumar, Munish Gupta and Hem Chander Garg

This paper aims at erosion wear experimentation conducted on two piping materials, namely SS202 and SS304 to establish the effect of rotational speed, concentration and time…

Abstract

Purpose

This paper aims at erosion wear experimentation conducted on two piping materials, namely SS202 and SS304 to establish the effect of rotational speed, concentration and time period.

Design/methodology/approach

Erosion wear because of slurry flow is investigated using a slurry erosion pot tester. Fly ash is taken as erodent material having different solid concentrations lie in range 30 to 60per cent (by weight). Experiments are performed at four different speeds, i.e. 600; 900; 1,200; and 1,500 rpm for time duration of 90, 120, 150 and 180 min, respectively. To enhance erosion wear resistance of both piping materials, high-velocity-oxy-fuel coating technique is used to deposit WC-10Co4Cr coating. The parametric influence of erosion wear is optimized using Taguchi method.

Findings

The results show that significant improvement in erosion wear resistance is observed by deposition of WC-10Co4Cr coating. It is observed that rotational speed is found as highly influencing parameter followed by concentration and time duration. Parametric investigation of erosion wear is helpful to develop a procedure for minimizing the erosion wear in pipeline for the flow of solid-liquid mixture.

Originality/value

Slurry erosion wear of WC-10Co4Cr coated stainless steel (SS202 and SS304) is substantiated by extensive microstructural analysis and optimization technique.

Details

Industrial Lubrication and Tribology, vol. 70 no. 9
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 3 April 2019

Jashanpreet Singh, Satish Kumar and S.K. Mohapatra

This study/paper aims to investigate the erosion wear performance of Ni-based coatings [Ni-Cr-O and NiCrBSiFe-WC(Co)] under sand-water slurry conditions.

Abstract

Purpose

This study/paper aims to investigate the erosion wear performance of Ni-based coatings [Ni-Cr-O and NiCrBSiFe-WC(Co)] under sand-water slurry conditions.

Design/methodology/approach

A high-velocity oxy-fuel (HVOF) process was used to deposit the Ni-based coatings [Ni-Cr-O and NiCrBSiFe-WC(Co)] on the surface of stainless steel (SS 316L) substrate. A Ducom TR-41 erosion tester was used to conduct the tribological experiments on bare/HVOF coated SS 316L. The erosion wear experiments were carried out for different time durations (1.30-3.00 h) at different impact angles (0-60°) by running the pot tester at different rotational speeds (600-1,500 rev/min). The solid concentration of sand slurry was taken in the range of 30-60 Wt.%. The surface roughness of Ni-based coated surfaces was also measured along the transverse length of the specimens.

Findings

Results show the arithmetic mean roughness (Ra) values of Ni-Cr-O and NiCrBSiFe-WC coated SS-316L were 7.04 and 6.67 µm, respectively. The erosion wear SS-316L was almost 3.5 ± 1.5 times greater than that of the NiCrBSiFe-WC coatings. NiBCrSi-WC(Co) sprayed SS-316L showed lower erosion wear than Ni-Cr-O sprayed SS-316L. Microscopically, the eroded Ni-Cr-O coating underwent plowing, microcutting and craters. Ni-Cr-O coating have shown the ductile nature of erosion wear mechanism. NiBCrSi-WC(Co) surface underwent craters, plowing, carbide/boride pullout, fractures and intact. Erosion wear mechanisms on the eroded surface of NiBCrSi-WC(Co) were neither purely ductile nor brittle.

Practical implications

It is a useful technique to estimate the erosion wear of hydraulic machinery coated with Ni-based coatings imposed under mining conditions.

Originality/value

The erosion wear performance of HVOF-sprayed Ni-Cr-O and NiCrBSiFe-WC(Co) powders was investigated through extensive experimentation, and the results are well supported by scanning electron micrographs and 3D topology.

Details

Industrial Lubrication and Tribology, vol. 71 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 25 September 2018

Gurmeet Singh, Satish Kumar and Satbir S. Sehgal

This paper aims to optimize the erosion wear analysis of slurry impeller material. Stainless steel (SS-410) was used as the pump impeller material. This erosion test was…

Abstract

Purpose

This paper aims to optimize the erosion wear analysis of slurry impeller material. Stainless steel (SS-410) was used as the pump impeller material. This erosion test was established to influence the rotational speed, solid concentration, time period and particle size. Fly ash was used as the erodent material.

Design/methodology/approach

The erosion wear experiments were performed at different particle size, rotational speed, time duration and solid concentration (by weight). These tests were performed at four different speeds of 750, 1,000, 1,250 and 1,500 rpm, and the time durations of these experiments are 75, 120,165 and 210 min. For protective coating, high-velocity oxygen-fuel spray process was used for depositing WC-10Co-4Cr coating on stainless steel. To investigate the influence of controlled process parameters on slurry erosion wear of pump impeller material, Taguchi method was used.

Findings

Results show that significant improvement in erosion wear resistance has been observed by using WC-10Co-4Cr coating. The process parameters affecting the erosion wear loss were in following order: time > rpm > concentration > particle size. The means of signal-to-noise ratio of stainless steel SS410 with and without coating vary from 93.56 to 54.02 and from 86.02 to 48.18, respectively.

Originality/value

For the erosion wear rate of both uncoated and coated stainless steel, the most powerful influencing factor was identified as time. The erosion test reveals that the coating exhibits ductile erosion mechanism and shows better erosion wear resistance (approximately two times) compared to uncoated stainless steel.

Details

Industrial Lubrication and Tribology, vol. 70 no. 9
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 10 June 2021

Jashanpreet Singh

The purpose of this paper is to carry out erosion wear investigation on high-velocity oxy-fuel (HVOF)-deposited 86WC-10Co4Cr and synergistic Ni/Chromia powder (i.e. 80Ni-20Cr2O3

Abstract

Purpose

The purpose of this paper is to carry out erosion wear investigation on high-velocity oxy-fuel (HVOF)-deposited 86WC-10Co4Cr and synergistic Ni/Chromia powder (i.e. 80Ni-20Cr2O3) on AISI 316L.

Design/methodology/approach

Design of experiments-artificial neural network (DOE-ANN) methodology was adopted to calculate the erosion wear. Taguchi’s orthogonal array L16 (42) was used to perform set-of-erosion experiments followed by lower-the-better rule. The artificial neural network (ANN) model is used on erosion wear data obtained from the experiments.

Findings

Experimental results indicate that 86WC-10Co4Cr provided better erosion wear resistance as compared to Ni/Chromia. The erosion wear of 86WC-10Co4Cr and synergistic Ni/Chromia coatings increases with an increase in time duration, solid concentration and time. The magnitude of erosion generated by ashes was comparatively lower than sand. The arithmetic mean roughness (Ra) of finished AISI 316L, 86WC-10Co4Cr and Ni/Chromia coating was found as 0.46 ± 0.13, 6.50 ± 0.16 and 7.04 ± 0.23 µm, respectively. Surface microhardness of AISI 316L, 86WC-10Co4Cr and Ni/Chromia coating was found as 197 ± 18, 1,156 ± 18 and 1,021± 21 HV, respectively.

Practical implications

The present results can be useful for estimation of erosion wear in slurry pumps used in mining industry for the conveying of sand and in thermal power plants for the conveying of ashes to the dyke area.

Originality/value

The erosion wear of HVOF-sprayed 86WC-10Co4Cr and Synergistic Ni/Chromia powders was studied experimentally as well as predicted by the ANN model, and wear mechanisms are well discussed by scanning electron micrographs.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 5 April 2022

Rajesh Kumar, Satish Kumar and Deepa Mudgal

The purpose of this paper is to investigate the erosion performance of high velocity oxy fuel- (HVOF) sprayed Al2O3–Cr2O3 composite coatings under silt slurry conditions.

Abstract

Purpose

The purpose of this paper is to investigate the erosion performance of high velocity oxy fuel- (HVOF) sprayed Al2O3–Cr2O3 composite coatings under silt slurry conditions.

Design/methodology/approach

The requisite HVOF composite coatings has been deposited on the stainless steel substrate (SS-304). The slurry erosion pot tester of make Ducom was used for conducting the silt slurry erosion tests on the required substrates. The comprehensive experiments were conducted at different particle size of silt in the range 212–250, 150–212, 53–106 µm, and the concentration of the silt ranged from 10%–40% by weight. The rotational speed of the pot tester has been varied between 500 and 1,500 revolutions per minute, and the test duration has been kept to 4 h.

Findings

The erosion wear resistance of the uncoated SS-304 has been greatly enhanced by the application of HVOF-sprayed Al2O3–Cr2O3 composite coatings. The addition of CeO2 has a significant impact in reducing the erosive wear caused by silt slurry. The composite coating powder composition of 65%Cr2O3 + 34.5%Al2O3 + 0.5%CeO2 has shown the highest erosion resistance.

Practical implications

The developed coatings have the potential to be used for hydro turbines as subjected to silt slurry conditions.

Originality/value

The erosion wear experiments are conducted comprehensively for coated and uncoated samples and the scanning electron micrographs supports the findings.

Details

Industrial Lubrication and Tribology, vol. 74 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 February 2016

Mehmet Bagci and Huseyin Imrek

This study aims to examine solid particle erosion behavior of novel hybrid composite materials where borax (B2O3) particles (∼150 μm) were added to glass fabric and epoxy resin at…

Abstract

Purpose

This study aims to examine solid particle erosion behavior of novel hybrid composite materials where borax (B2O3) particles (∼150 μm) were added to glass fabric and epoxy resin at an amount of 15 and 30 per cent.

Design/methodology/approach

The tests that involved slightly rounded and irregular Al2O3 particles having two erodent sizes (200, 400 μm) were conducted at these operational conditions; namely, three impact velocities (23, 34, 53 m/s), two fabric directions (0/90/0, 45/−45/45) and three impingement angles (30°, 60°, 90°). In addition, the design of experiments, which utilizes Taguchi’s robust orthogonal arrays approach, was used and an optimum parameter combination was established, which had a minimum erosion rate. Moreover, scanning electron microscope and X-ray diffraction views show the visual effect of filler material.

Findings

All test specimens regardless of their dissimilar characteristics displayed maximum erosion rate at 30° impingement angle. Test specimens with 45/−45/45 fabric direction are more wear-resistant than their counterparts with 0/90/0 fabric direction. The erosion wear of glass fabric reinforced epoxy (GF/EP) composites whose matrix had 15 per cent addition of borax particles was higher than that of neat GF/EP composites. In addition, new composite material formed by including borax particles at a rate of 30 per cent of resin leads to a reduction in erosion rates.

Originality/value

While fabric-reinforced polymers take place in most of the studies conducted on erosive wear of composites, studies involving erosion on composites with filler materials can hardly be encountered.

Details

Industrial Lubrication and Tribology, vol. 68 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 25 October 2019

Gurmeet Singh, Satish Kumar, Satbir Singh Sehgal and Shashi Bhushan Prasad

This paper aims to depict the erosion performance of two HVOF-coated micron layers (Colmonoy-88 and Stellite-6) on pump impeller steel (SS-410) by using Taguchi's method…

Abstract

Purpose

This paper aims to depict the erosion performance of two HVOF-coated micron layers (Colmonoy-88 and Stellite-6) on pump impeller steel (SS-410) by using Taguchi's method. Taguchi's array (L16) was used to optimize the erosion wear (in terms of weight loss) by using four influencing parameters such as rotational speed, solid concentration, average particle size and time which were varied at four different levels.

Design/methodology/approach

The experiments were carried out by using a Ducom slurry tester with rotational speed in the range of 750-1,500 rpm, solid concentration of 35-65 per cent by weight, time period of 75-210 min and average particle sizes in the range of < 53 to 250 µm. Bottom Ash with a nominal size range of < 53 to 250 µm was used as erodent. The process parameters were optimized by using Taguchi's method. The ANOVA method was used to validate the results given by Taguchi's method.

Findings

The results revealed that the presence of both carbides and borides and the additional presence of Cr in Colmonoy-88 coating enhancing the slurry erosion resistance of Colmonoy-88 coating. Moreover, the chromium and tungsten carbide particles help in increasing the bond strength between the coating and the substrate material. Further, it was also found that the time was the most dominant factor as compared to other factors.

Originality/value

The very less work has been reported on optimization of erosion wear response of Colmonoy-88 and Stellite-6 coatings by using different design of experiment techniques. Further, the erosion wear mechanism of both coatings has been studied by using image j analysis software.

Details

Industrial Lubrication and Tribology, vol. 72 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 3 June 2014

Surajit Purkayastha and Dheerendra Kumar Dwivedi

– This paper aims to deal with the study of effect of cerium oxide (CeO2) modification on the sand slurry erosion resistance of Ni – tungsten carbide (WC) coatings.

Abstract

Purpose

This paper aims to deal with the study of effect of cerium oxide (CeO2) modification on the sand slurry erosion resistance of Ni – tungsten carbide (WC) coatings.

Design/methodology/approach

Flame-sprayed conventional and CeO2-modified Ni–WC coatings were developed on a mild steel substrate. Slurry erosion tests were carried out in an in-house-designed and fabricated pot-type slurry erosion test rig to evaluate wear behavior of conventional and modified coatings. The erosive wear test was conducted using 5 per cent silica sand slurry at 850 rpm.

Findings

Modified coatings exhibited increased hardness as compared to the conventional coating. Slurry erosion resistance of most modified coatings was superior to that of the unmodified coating. Hardness of coating doped with 0.9 per cent CeO2 was highest among all coatings, and concomitantly this composition also showed the least wear. Scanning electron microscopy (SEM) revealed that microcutting was much less in the modified coating.

Originality/value

Slurry erosion wear of Ni–WC flame-sprayed coatings in sand slurry media is substantiated by extensive SEM study.

Details

Industrial Lubrication and Tribology, vol. 66 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 March 2021

Gaurav Prashar and Hitesh Vasudev

In the present study, Al2O3 coatings were deposited on stainless steel AISI-304 material by using atmospheric plasma spraying technique to combat high temperature solid particle…

Abstract

Purpose

In the present study, Al2O3 coatings were deposited on stainless steel AISI-304 material by using atmospheric plasma spraying technique to combat high temperature solid particle erosion. The present aims at the performance analysis of Al2O3 coatings at high temperature conditions.

Design/methodology/approach

The erosion studies were carried out at a temperature of 400°C by using a hot air-jet erosion tester for 30° and 90° impingement angles. The possible erosion mechanisms were analyzed from scanning electron microscope (SEM) micrographs. Surface characterization of the powder and coatings were conducted by using an X-ray diffractometer, SEM, equipped with an energy dispersive X-ray analyzer. The porosity, surface roughness and micro-hardness of the as-sprayed coating were measured. This paper discusses outcomes of the commonly used thermal spray technology, namely, the plasma spray method to provide protection against erosion.

Findings

The plasma spraying method was used to successfully deposit Al2O3 coating onto the AISI 304 substrate material. Detailed microstructural and mechanical investigations were carried out to understand the structure-property correlations. Major findings were summarized as under: the erosive wear test results indicate that the plasma sprayed coating could protect the substrate at both 30° and 90° impact angles. The coating shows better resistance at an impact angle of 30° compared with 90°, which is related to the pinning and shielding effect of the alumina particle. The major erosion wear mechanisms of Al2O3 coating were micro-cutting, micro-ploughing, splat removal and detachment of Al2O3 hard particles.

Originality/value

In the current study, the authors have followed the standard testing method of hot air jet erosion test as per American society for testing of materials G76-02 standard and reported the erosion behavior of the eroded samples. The coating was not removed at all even after the erosion test duration i.e. 10 min. The erosion test was continued till 3 h to understand the evolution of coatings and the same has been explained in the erosion mechanism. The outcome of the present study may be used to minimize the high temperature erosion of AISI-304 substrate.

Details

World Journal of Engineering, vol. 18 no. 5
Type: Research Article
ISSN: 1708-5284

Keywords

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