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1 – 10 of 235
Article
Publication date: 2 February 2023

Shanmugan Subramani and Mutharasu Devarajan

Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested…

Abstract

Purpose

Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested and reported. The purpose of this paper is suggesting thin film-based TIM to sustain the light-emiting diode (LED) performance and electronic device miniaturization.

Design/methodology/approach

Consequently, ZnO thin film at various thicknesses was prepared by chemical vapour deposition (CVD) method and tested their thermal behaviour using thermal transient analysis as solid TIM for high-power LED.

Findings

Low value in total thermal resistance (Rth-tot) was observed for ZnO thin film boundary condition than bare Al boundary condition. The measured interface (ZnO thin film) resistance {(Rth-bhs) thermal resistance of the interface layer (thin film) placed between metal core printed circuit board (MCPCB) board and Al substrates} was nearly equal to Ag paste boundary condition and showed low values for ZnO film prepared at 30 min process time measured at 700 mA. The TJ value of LED mounted on ZnO thin film (prepared at 30 min.) coated Al substrates was measured to be 74.8°C. High value in junction temperature difference (ΔTJ) of about 4.7°C was noticed with 30 min processed ZnO thin film when compared with Al boundary condition. Low correlated colour temperature and high luminous flux values of tested LED were also observed with ZnO thin film boundary condition (processed at 30 min) compared with both Al substrate and Ag paste boundary condition.

Originality/value

Overall, 30 min CVD processed ZnO thin film would be an alternative for commercial TIM to achieve efficient thermal management. This will increase the life span of the LED as the proposed material decreases the TJ values.

Details

Microelectronics International, vol. 41 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 19 February 2024

Bassem Assfour, Bassam Abdallah, Hour Krajian, Mahmoud Kakhia, Karam Masloub and Walaa Zetoune

The purpose of this study is to investigate the structural, surface roughness and corrosion properties of the zirconium oxide thin films deposited onto SS304 substrates using the…

Abstract

Purpose

The purpose of this study is to investigate the structural, surface roughness and corrosion properties of the zirconium oxide thin films deposited onto SS304 substrates using the direct current (DC) magnetron sputtering technique.

Design/methodology/approach

DC sputtering at different powers – 80, 100 and 120 W – was used to deposit ZrO2 thin films onto different substrates (Si/SS304) without annealing of the substrate. Atomic force microscope (AFM), energy-dispersive X-ray spectroscopy (EDS), Tafel extrapolation and contact angle techniques were applied to investigate the surface roughness, chemical compositions, corrosion behavior and hydrophobicity of these films.

Findings

Results showed that the thickness of the deposited film increased with power increase, while the corrosion current decreased with power increase. AFM images indicated that the surface roughness decreased with an increase in DC power. EDS analysis showed that the thin film has a stoichiometric ZrO2 (Zr:O 1:2) composition with basic uniformity. Water contact angle measurements indicated that the hydrophobicity of the synthesized films decreased with an increase in surface roughness.

Originality/value

DC magnetron sputtering technique is infrequently used to deposition thin films. The obtained thin films showed good hydrophobic and anticorrosion properties. Finally, results are compared with other deposition techniques.

Details

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

Keywords

Article
Publication date: 5 June 2023

Yidong Zhang

The purpose of this paper is to study the electronic transport performance of Ag-ZnO film under dark and UV light conditions.

Abstract

Purpose

The purpose of this paper is to study the electronic transport performance of Ag-ZnO film under dark and UV light conditions.

Design/methodology/approach

Ag-doped ZnO thin films were prepared on fluorine thin oxide (FTO) substrates by sol-gel method. The crystal structure of ZnO and Ag-ZnO powders was tested by X-ray diffraction with Cu Kα radiation. The absorption spectra of ZnO and Ag-ZnO films were recorded by a UV–visible spectrophotometer. The micro electrical transport performance of Ag-ZnO thin films in dark and light state was investigated by photoassisted conductive atomic force microscope (PC-AFM).

Findings

The results show that the dark reverse current of Ag-ZnO films does not increase, but the reverse current increases significantly under illumination, indicating that the response of Ag-ZnO films to light is greatly improved, owing to the formation of Ohmic contact.

Originality/value

To the best of the author’s knowledge, the micro electrical transport performance of Ag-ZnO thin films in dark and light state was firstly investigated by PC-AFM.

Details

Microelectronics International, vol. 41 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 30 September 2022

Amirul Syafiq, Vengadaesvaran Balakrishnan and Nasrudin Abd. Rahim

This paper aims to design the nano-titanium dioxide (TiO2) coating system which has superhydrophilic property, self-cleaning mechanism and antifog property as well as strong…

Abstract

Purpose

This paper aims to design the nano-titanium dioxide (TiO2) coating system which has superhydrophilic property, self-cleaning mechanism and antifog property as well as strong adhesion on glass substrate.

Design/methodology/approach

Two hydrophilic materials have been used such as TiO2 nanoparticles as fillers and hydrophilic copolymer, Pluronic F-127 by using simple sol–gel approach. The prepared solution was applied onto glass through dip- and spray-coating techniques and then left for drying at ambient temperature.

Findings

The nano-TiO2 superhydrophilic coating has achieved the water contact angle of 4.9° ± 0.5°. The superhydrophilic coating showed great self-cleaning effect against concentrated syrup and methylene blue where thin layer of water washes the dirt contaminants away. The nano-TiO2 coating exhibits great antifog performance that maintains high transparency of around 89% when the coated glass is placed above hot-fog vapor for 10 min. The fog droplets were condensed into water film which allowed the transmission of light through the glass. The strong adhesion of coated glass shows no total failure at scratch profile when impacted with scratch load of 500, 800 and 1,200 mN.

Research limitations/implications

Findings will be useful in the development of self-cleaning superhydrophilic coating that is applicable on building glass and photovoltaic panel.

Practical implications

The developed nano-TiO2 coating is developed by the combination of hydrophilic organic copolymer–inorganic TiO2 network to achieve great superhydrophilic property, optimum self-cleaning ability and supreme antifog performance.

Social implications

The findings will be useful for residents in building glass window where the application will reduce dust accumulation and keep the glass clean for longer period.

Originality/value

The synthesis of nano-TiO2 superhydrophilic coating which can be sprayed on large glass panel and cured at ambient temperature.

Article
Publication date: 21 December 2022

Vimal Kumar Deshmukh, Mridul Singh Rajput and H.K. Narang

The purpose of this paper is to present current state of understanding on jet electrodeposition manufacturing; to compare various experimental parameters and their implication on…

Abstract

Purpose

The purpose of this paper is to present current state of understanding on jet electrodeposition manufacturing; to compare various experimental parameters and their implication on as deposited features; and to understand the characteristics of jet electrodeposition deposition defects and its preventive procedures through available research articles.

Design/methodology/approach

A systematic review has been done based on available research articles focused on jet electrodeposition and its characteristics. The review begins with a brief introduction to micro-electrodeposition and high-speed selective jet electrodeposition (HSSJED). The research and developments on how jet electrochemical manufacturing are clustered with conventional micro-electrodeposition and their developments. Furthermore, this study converges on comparative analysis on HSSJED and recent research trends in high-speed jet electrodeposition of metals, their alloys and composites and presents potential perspectives for the future research direction in the final section.

Findings

Edge defect, optimum nozzle height and controlled deposition remain major challenges in electrochemical manufacturing. On-situ deposition can be used as initial structural material for micro and nanoelectronic devices. Integration of ultrasonic, laser and acoustic source to jet electrochemical manufacturing are current trends that are promising enhanced homogeneity, controlled density and porosity with high precision manufacturing.

Originality/value

This paper discusses the key issue associated to high-speed jet electrodeposition process. Emphasis has been given to various electrochemical parameters and their effect on deposition. Pros and cons of variations in electrochemical parameters have been studied by comparing the available reports on experimental investigations. Defects and their preventive measures have also been discussed. This review presented a summary of past achievements and recent advancements in the field of jet electrochemical manufacturing.

Article
Publication date: 16 August 2023

Yuan Liu, Chang Dong, Xianzhang Wang, Xiao Sang, Liran Ma, Xuefeng Xu and Yu Tian

The purpose of this study is to reveal the underlying mechanism in film formation of oil-in-water (O/W) emulsion.

Abstract

Purpose

The purpose of this study is to reveal the underlying mechanism in film formation of oil-in-water (O/W) emulsion.

Design/methodology/approach

This study focuses on the film forming characteristics of O/W emulsion between the surface of a steel ball and a glass disc coated with chromium. The lubricant film thicknesses of O/W emulsion with various mechanical stirring strength were discussed, which were observed by technique of relative optical interference intensity.

Findings

The authors directly observed the oil pool in the contact area, finding the size of oil pool was closely related to the film-forming ability of emulsion. Enrichment phenomenon occurs in oil pool, which was caused by phase inversion. Further investigations revealed that the emulsion is stable with strong stirring strength, resulting in a smaller oil pool size and worse film forming ability.

Originality/value

With the wide usage of O/W emulsion in both biological and industrial systems, the ability of emulsion film formation is considered as an important factor to evaluate the lubrication effectiveness.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2022-0354/

Details

Industrial Lubrication and Tribology, vol. 75 no. 8
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 22 November 2023

Shoufan Cao, Zhang Xu, Yi Liang and Stefano Mischler

The aim of this study is to experimentally analyze the friction and wear responses of different steels to different surface films generated in oil-lubricated tribological contacts.

Abstract

Purpose

The aim of this study is to experimentally analyze the friction and wear responses of different steels to different surface films generated in oil-lubricated tribological contacts.

Design/methodology/approach

Tribological experiments were conducted using a 100Cr6 bearing ball sliding against a V155 carbon steel disk and 316L stainless steel disk, respectively. Lubricants with additives known to form zinc dialkyl-dithiophosphate (ZDDP) or Ca tribofilms were used.

Findings

Both of the ZDDP and Ca tribofilms helped stabilize the friction coefficient of the carbon steel and stainless steel. The ZDDP tribofilm could effectively protect the carbon steel from wear, in contrast to the stainless steel, whereas the wear of both carbon steel and stainless steel could be significantly reduced by the Ca tribofilm. In the case of neither ZDDP nor Ca tribofilms formation, the 100Cr6 ball was worn by the V155 disk and generated a special surface topography. A polishing wear mechanism was proposed to explain the wear of the 100Cr6 ball.

Originality/value

This study clearly shows the different friction and wear responses of steels to the different surface films and the response is dependent on the tested steel.

Details

Industrial Lubrication and Tribology, vol. 76 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 31 August 2023

Shaoxuan Li, Yi Xu, Haiqing Xia, Jing Duan, Yingjie Yu, Xingyun Duan, Pengfei Shi and Jiancheng Tang

Tantalum is a kind of metal material with moderate hardness, high ductility, small thermal expansion coefficient, excellent corrosion resistance and outstanding biocompatibility…

46

Abstract

Purpose

Tantalum is a kind of metal material with moderate hardness, high ductility, small thermal expansion coefficient, excellent corrosion resistance and outstanding biocompatibility. The purpose of this study is that its tribological performance could be tested and analyzed so as to use it in different fields.

Design/methodology/approach

The friction resistance of a-Ta under dry friction conditions was tested at different roads. The relationships between load and friction coefficient, wear rate and two-dimensional shape of wear scars were studied.

Findings

The stable Ta2O5 film with lubrication effect was generated in the process of friction. And, the larger the test load, the more Ta2O5 would be generated.

Originality/value

This work lays a theoretical foundation for tantalum as an excellent wear-resistant material.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2023-0047/

Details

Industrial Lubrication and Tribology, vol. 75 no. 8
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 29 August 2023

Junjie Niu, Weimin Sang, Qilei Guo, Aoxiang Qiu and Dazhi Shi

This paper aims to propose a method of the safety boundary protection for unmanned aerial vehicles (UAVs) in the icing conditions.

61

Abstract

Purpose

This paper aims to propose a method of the safety boundary protection for unmanned aerial vehicles (UAVs) in the icing conditions.

Design/methodology/approach

Forty icing conditions were sampled in the continuous maximum icing conditions in the Appendix C of the Federal Aviation Regulation Part 25. Icing numerical simulations were carried out for the 40 samples and the anti-icing thermal load distribution in full evaporation mode were obtained. Based on the obtained anti-icing thermal load distribution, the surrogated model of the anti-icing thermal load distribution was established with proper orthogonal decomposition and Kriging interpolation. The weather research and forecasting (WRF) model was used for meteorological simulations to obtain the icing meteorological conditions in the target area. With the obtained icing conditions and surrogated model, the anti-icing thermal load distribution in the target area and the variation with time can be determined. According to the energy supply of the UAVs, the graded safety boundaries can be obtained.

Findings

The surrogated model can predict the effects of five factors, such as temperature, velocity, pressure, median volume diameter (MVD) and liquid water content (LWC), on the anti-icing thermal load quickly and accurately. The simulated results of the WRF mode agree well with the observed results. The method can obtain the graded safety boundaries.

Originality/value

The method has a reference significant for the safety of the UAVs with the limited energy supply in the icing conditions.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 10
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 30 August 2023

Jian Wei, XiaoYue Sun, Jing Tian and CaiHong Liu

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

97

Abstract

Purpose

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

Design/methodology/approach

Establish a model of transient mixed lubrication, solve the transient Reynolds equation, consider the effect of temperature rise at the seal interfaces, and determine the behavior of the seal interfaces, such as film thickness and fluid pressure. Evaluation with friction and leakage rate, calculate the variation of sealing performance with reciprocating velocity under different working conditions, and verify it through bench experiments.

Findings

Within a reciprocating stroke, the frictional force decreases with increasing velocity, and the frictional force of the outstroke is greater than that of the instroke; at the time of the stroke transition, the fluid pressure is smallest and the rough peak contact pressure is greatest. At present, the dynamic pressure effect of fluids is the largest, and the friction force also increases, which increases the risk of material wear and failure. Friction and leakage increase with increasing pressure and root mean square roughness. As temperature increases, friction increases and leakage decreases. In studying the performance variations of seal components through a reciprocating sealing experiment, it was found that the friction force decreases with increasing velocity, which is consistent with the calculated results and more similar to the calculated results considering the temperature rise.

Originality/value

This study provides a reference for the study of transient sealing performance.

Details

Industrial Lubrication and Tribology, vol. 75 no. 9
Type: Research Article
ISSN: 0036-8792

Keywords

1 – 10 of 235