The present work investigates correlation between the structural and tribological behavior of pure Ni coating and Ni-WSe2 composite coatings at different WSe2 loading level (0, 0.1, 0.2, 0.5, 1 and 2 ...g/l). The developed coatings were characterized by X-ray diffraction technique (XRD), field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS) for phase, structure and compositional verifications, respectively. Structural and phase evolution of the coatings were correlated with roughness, microhardness and wear behavior. Characterization confirmed that beyond 0.5 g/l WSe2 content in the electrolyte, the composite coatings turned brittle and non-uniform with high surface roughness. The maximum hardness of 665 HV was observed in case of Ni-0.5 g/l WSe2 coating, whereas, the lowest average coefficient of friction of 0.068 was found in Ni-1 g/l WSe2 followed by 0.07 for Ni-0.5 g/l WSe2 coating. It was observed that Ni-0.5 g/l WSe2 coating possessed optimum mechanical properties and wear resistance.
The present work depicts electro-codeposition of copper along with Al (size ~ 20 nm) and V2O5 (size ~ 350 nm) particles as second phase reinforcements on copper substrate. Different compositions of ...Cu-Al-V2O5 composite coatings were formed from acidic electrolyte with addition of 5 g/l Al and 10 g/l V2O5 particles in the deposition bath with 8 A/dm2 current density both in the presence and absence of CTAB. Field emission scanning electron microscope (FESEM) image of non-CTAB added coatings show coarser structure compared to CTAB added coatings. Mechanical characterizations of the coatings portray better hardness and wear resistance of composite coatings compared to unreinforced Cu coated sample. Among the non-CTAB and CTAB assisted coatings, CTAB treated specimens have better mechanical properties in terms of hardness and wear resistance compared to non-CTAB ones due to finer coating matrix and formation of (220) texture. The downgrading of electrical conductivity values of the composite coatings was due to the codeposition of insulating V2O5 and finer coating matrix. Aluminum in the coating tends to maintain the electrical conductivity but provides little strengthening effect.
Cu/Al
2
O
3
composite coatings were prepared from acidic copper sulfate bath containing ultrafine Al
2
O
3
particles by direct current plating method to increase the surface-mechanical property of Cu ...for its possible use as electrical contact. Effect of ultrafine Al
2
O
3
particle concentration in electrolyte and deposition current density on the surface-mechanical properties of the coatings was investigated. Coatings were characterized by scanning electron microscopy and X-ray diffraction (XRD) techniques for the purpose of surface morphology and phase study. From XRD data, crystallographic texture of the coating was also analyzed. To study the mechanical properties, microhardness testing, adhesion, and wear test were carried out. Improved hardness of the resultant coatings was observed and was correlated with the wt pct of ultrafine particle in the Cu matrix, matrix structure, and crystallographic orientation. Better wear property of the composite coating was also reported from the wear plot and wear track morphology. Altogether, better coating property was attributed toward finer matrix, hard reinforced phase, and preferred orientation in selected conditions. Electrical conductivity of the coating was affected by grain size and second-phase concentration, and the values obtained were in the usable range required for electrical applications.
Glass fibre reinforced epoxy composite (GRE) pipe exhibits degrading rate of deterioration of mechanical properties like inter laminar shear strength (ILSS) and modulus after one year of sea water ...flow under fluctuating temperature. Glass transition temperatures (Tg) of the treated pipe samples decrease compared to as-cured one. FTIR spectra of GRE samples reveal the mechanism of Tg variation. Depths of penetrations of various salt components as established through EDS analysis is found maximum for ‘Ca’ and minimum for ‘Na’. Cell culture test of the used sea water confirms ‘Na’ and ‘K’ are the favourable nutrients for growth of micro-organisms which lock these salts retarding their permeation to composite body. Deposition of ‘Na’ and ‘K’, as observed through XPS analysis, causes the rate of property deterioration of the pipe. The SEM fractographs of the treated pipe samples indicate the failure modes in agreement with the trends of mechanical properties. As per the present experimental findings, GRE composite can be chosen for piping applications for prolonged flow of sea water in desalination industries.
•GRE composite exhibits decreasing rate of property deterioration due to deposition of salt components like ‘Na’ and ‘K’.•Sustainable use of the GRE composite pipe is claimed under continuous prolonged flow of sea water.•The present research establishes 23% reduction (maximum) of ILSS of composite pipe, even after one year of sea water flow.•GRE composite can be chosen for prolonged transport of sea water in desalination industries.
The current investigation is an effort of correlating the grain growth, crystallographic orientation and second-phase Y
2
O
3
particles to the mechanical properties of the electrodeposited pure ...copper (Cu) and Cu-Y
2
O
3
coatings. Energy-dispersive spectrum and elemental mapping confirm the codeposition of Y
2
O
3
in the composite coating matrix, which indeed justifies the composite (Cu-Y
2
O
3
) coating. Both pure Cu and Cu-Y
2
O
3
coatings have (101) preferred orientation; however, the volume fraction is found comparatively lower in composite coating. Both microstructural and textural characterization through electron backscattered diffraction technique show significant grain refinement in case of Cu-Y
2
O
3
composite coating compared to pure Cu coating, and prominent 〈011〉 fiber texture is observed in case of pure Cu coating compared to composite coating. By the addition of second-phase Y
2
O
3
in the matrix, the 〈011〉 fiber texture is disintegrated and concentrated at
ϕ
1
= 37°,
ϕ
= 45°,
ϕ
2
= 0°. Despite lower volume fraction of 〈011〉 fiber texture, better mechanical properties (hardness and wear resistance) of the composite coating compared to pure Cu coating can be attributed to finer grain size, higher misorientation angle and incorporation of second-phase Y
2
O
3
particles.
The present work discusses the effect of structure and morphology of rust on the corrosion behavior of a mild steel and an interstitial free steel exposed to open atmosphere for 2 years involving ...extreme weather conditions, where temperature varies from 2-3 to 45 °C, rainfall varies from 10 to 320 mm and humidity varies from ~ 20 to 75%. Effect of duration of atmospheric exposure, change in morphological characteristics of rust, and atmospheric parameters, such as temperature, humidity, rain and SO
2
content on the corrosion behavior of both the steels was analyzed. Corrosion resistance of the interstitial free steel was better than the mild steel due to lower carbon content and better compactness of the rusts formed on the interstitial free steel.
The present study explored the possibilities of improvement in the surface-mechanical properties of electrodeposited Cu-SiO
2
composite coating and its underlying mechanism. Composite coatings were ...developed using SiO
2
-dispersed acidic copper sulfate electrolyte by direct current and pulse-current electro-codeposition techniques with variation of pulse frequencies at a fixed duty cycle. X-ray diffraction analysis of the coatings revealed information regarding the presence of various phases and crystallographic orientations of the deposited Cu matrix. Scanning electron microscopy and energy dispersive x-ray spectroscopy techniques were used to investigate the surface morphology and chemical composition of the coatings, respectively, and it was observed that SiO
2
particles were uniformly distributed in the composite coatings. Surface roughness was found to be reduced with the increasing pulse frequency. The Vickers microhardness and ball-on-plate wear study showed improvement in surface-mechanical properties due to the formation of fine Cu matrix, dispersion strengthening due to homogeneously distributed SiO
2
particles, and the preferred orientation of the Cu matrix. Marginal decrease in electrical conductivity with the increasing SiO
2
content and pulse frequency was observed from the four-probe electrical conductivity measurement technique.
The present work describes processing and properties of Cu-TiO sub(2) electrodeposited coating on copper substrate with optimized current density and ultrafine ceramic TiO sub(2) powder in the ...plating bath. Direct current electrodeposition process was employed to develop the composite coating with Cu matrix and ceramic oxide (TiO sub(2)) nanoparticles as reinforcement on copper substrate. The coatings were developed with 0 (unreinforced), 10 and 30 g l super( )-1TiO sub(2) powder in bath, at four different current densities (5, 8, 11 and 14 A dm super( )-2 to study the effect of current density and particle concentration in bath on the structure and properties of the developed coatings. Phase, microstructure and compositional analysis of the coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. Hardness and wear resistance of the coatings were analysed by using microhardness tester and ball on plate wear tester and improvement in these properties was observed due to particle reinforcement and crystallographic texture.
Cu/Al^sub 2^O3 composite coatings were prepared from acidic copper sulfate bath containing ultrafine Al^sub 2^O3 particles by direct current plating method to increase the surface-mechanical property ...of Cu for its possible use as electrical contact. Effect of ultrafine Al^sub 2^O3 particle concentration in electrolyte and deposition current density on the surface-mechanical properties of the coatings was investigated. Coatings were characterized by scanning electron microscopy and X-ray diffraction (XRD) techniques for the purpose of surface morphology and phase study. From XRD data, crystallographic texture of the coating was also analyzed. To study the mechanical properties, microhardness testing, adhesion, and wear test were carried out. Improved hardness of the resultant coatings was observed and was correlated with the wt pct of ultrafine particle in the Cu matrix, matrix structure, and crystallographic orientation. Better wear property of the composite coating was also reported from the wear plot and wear track morphology. Altogether, better coating property was attributed toward finer matrix, hard reinforced phase, and preferred orientation in selected conditions. Electrical conductivity of the coating was affected by grain size and second-phase concentration, and the values obtained were in the usable range required for electrical applications.
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