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Article
Publication date: 8 January 2018

Yanfei Yang, Xiaobo Wang, Sen Mei, Xing Zhu, Shiqiang Chen, Peng Xiong, Zhihai Hu, Kun Xiong and Dong Song Yuan

The purpose of this paper is to investigate the tribological performance and mechanisms of BN/calcium borate nanocomposites (BCBNs) as additives in lubricating oil.

243

Abstract

Purpose

The purpose of this paper is to investigate the tribological performance and mechanisms of BN/calcium borate nanocomposites (BCBNs) as additives in lubricating oil.

Design/methodology/approach

BCBNs were prepared by heterogeneous deposition method. And the morphology and structure of samples were analysed by transmission electron microscopy, Fourier transform infrared spectra and X-ray powder diffraction pattern. The maximum non-seizure load (PB) of samples was tested using four-ball friction tester. The average friction coefficients and wear tracks were obtained. In addition, tribological mechanism was also investigated using optical microscope, energy dispersive spectroscopy and X-ray photoelectron spectroscope.

Findings

It was found that the nanocomposites present core-shell nanostructure with the thickness of shell around 12 nm and the diameter of particles 100-200 nm, and tribological tests indicate that the PB value of BCBNs was increased by 113 per cent, whereas the average friction coefficient was decreased by 23.6 per cent and the bloom’s wear area was also decreased by 25.2 per cent.

Originality/value

This paper involves investigation on tribological properties and mechanism of the BCBNs with core-shell structure.

Details

Industrial Lubrication and Tribology, vol. 70 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 31 January 2020

Xiaobo Wang, Wen Zhan and Boyi Gui

The purpose of this paper is to develop a chrome-free and phosphorus-free chemical conversion coating with good corrosion resistance, a novel chemical conversion coating was…

177

Abstract

Purpose

The purpose of this paper is to develop a chrome-free and phosphorus-free chemical conversion coating with good corrosion resistance, a novel chemical conversion coating was prepared by adding cerium nitrate hexahydrate and salicylic acid in the treatment solution containing titanium/zirconium ions on 6061 aluminum alloy.

Design/methodology/approach

Compared with the AA6061 aluminum alloy matrix, the self-corrosion potential of the conversion coating is significantly positively shifted, the self-corrosion current density is greatly reduced and its corrosion resistance is significantly improved. Morphology and composition of the conversion coatings were observed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The microdomain structure of conversion coatings at different formation stages was analyzed by electron probe microanalyzer.

Findings

An optimized preparation technique of titanium–zirconium chemical conversion coating for AA6061 aluminum alloy is obtained: H2TiF6 4 mL/L, H2ZrF6 0.4 mL/L, salicylic acid 0.35 g/L, Ce(NO3)3·6H2O 0.14 g/L, reaction temperature 30°C, reaction time 120 s and pH 4.0.

Originality/value

The coating forms on the Al(Fe)Si intermetallic compound, and Ce3+ is preferentially adsorbed on the intermetallic compound. The hydrolysis of Ce3+ causes the local pH of the solution to decrease, which promotes matrix dissolution and charge migration. As the microanode/microcathode reaction occurs, the local pH of the solution increases, and Al2O3/ZrO2/TiO2 begins to deposit on the surface of the metal substrate.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 2
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 14 February 2019

Xiaobo Wang, Zhipeng Li, Wen Zhan, Jesong Tu, Xiaohua Zuo, Xiangyi Deng and Boyi Gui

This study aims to expand the reliability and special functions of lightweight materials for high-end equipment and green manufacturing, so that it is the first such research to…

217

Abstract

Purpose

This study aims to expand the reliability and special functions of lightweight materials for high-end equipment and green manufacturing, so that it is the first such research to carry out nano-composite technology of nickel-coated carbon nanotubes (Ni-CNTs)-based titanium-zirconium chemical conversion on aluminum alloy substrate.

Design/methodology/approach

Corrosion behavior of various coatings was investigated using dropping corrosion test, linear polarization and electrochemical impedance spectroscopy. The results showed that the corrosion resistance of the nano-composite conversion coatings was significantly improved to compare with the conventional titanium-zirconium conversion coating. The morphology and microdomain characteristics of the nano-composite conversion coatings were characterized by SEM/eds/EPMA, which indicated that the CNT or Ni-CNTs addition promoting the integrity coverage of coatings in a short time.

Findings

Surface morphology of titanium-zirconium (Ti-Zr)/Ni-CNT specimens exhibited smooth, compact and little pores. The nano-composite conversion coatings are mainly composed of Al, O, C and Ti elements and contain a small amount of F and Zr elements, which illuminated that CNT or Ni-CNT addition could co-deposit with aluminum and titanium metal oxides.

Originality/value

The study of corrosion resistance of nano-composite conversion coatings and the micro-zone film-formation characteristics would be provided theoretical support for the development of basic research on surface treatment of aluminum alloys.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 8 April 2014

Junming Wang, Jianhua Wang, Chunsheng Li, Gaiqing Zhao and Xiaobo Wang

The purpose of this paper is to present the tribological, anticorrosion and antirust properties of three 2,5-dimercapto-1,3,4-thiadiazole (DMTD) derivatives as water-soluble…

455

Abstract

Purpose

The purpose of this paper is to present the tribological, anticorrosion and antirust properties of three 2,5-dimercapto-1,3,4-thiadiazole (DMTD) derivatives as water-soluble additives in water–glycol hydraulic fluid.

Design/methodology/approach

DMTD derivatives possessing excellent corrosion inhibiting and extreme-pressure (EP) properties have long been used as metal passivators and load-carrying additives in lubricating oils and grease. However, there are seldom literatures about DMTD derivatives as water-soluble lubricant additives as yet. In this work, three DMTD derivatives were synthesized and investigated as water-soluble additives in the water–glycol hydraulic fluid. Their tribological properties were evaluated in detail by four-ball wear test machine and Optimol SRV-IV oscillating friction and wear tester. Meanwhile, their anticorrosion and antirust properties were also investigated by copper strip corrosive tests and antirust tests, respectively. The worn surfaces were analyzed by scanning electron microscope and X-ray photonelectron spectroscope, and the EP, antiwear and friction-reducing mechanisms were primarily proposed.

Findings

The synthesized three DMTD derivatives (coded as A, B and C) have excellent solubility in the base liquid of the water–glycol hydraulic fluid. The experimental results demonstrated that all these compounds, especially A, could remarkably improve the EP, antiwear and friction-reducing properties of the base liquid. Furthermore, they all have perfect copper corrosion inhibiting and antirust properties with low adding concentration (< 3 weight per cent) in the base liquid and hence could be used as multifunctional additives in the water–glycol hydraulic fluid.

Research limitations/implications

This research only focused on the synthesized DMTD derivatives. If possible, some other thiadiazole derivatives also should be investigated.

Practical implications

The synthesized DMTD derivatives, especially compound A, can be used as multifunctional water-soluble additives in the water–glycol hydraulic fluid.

Originality/value

In this paper, three DMTD derivatives were synthesized and their tribological behaviors as water-soluble lubricant additives were investigated for the first time. In addition, the EP, antiwear and friction-reducing mechanisms were also put forward.

Details

Industrial Lubrication and Tribology, vol. 66 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 17 August 2010

Jianhua Wang, Jinlong Li, Xiaobo Wang and Weimin Liu

The purpose of this paper is to prepare water‐soluble TiO2 nanoparticles and evaluate the tribological properties as additives in water.

617

Abstract

Purpose

The purpose of this paper is to prepare water‐soluble TiO2 nanoparticles and evaluate the tribological properties as additives in water.

Design/methodology/approach

Nanoparticles present excellent friction‐reducing and antiwear properties as additives in base oils. However, there are seldom literatures about the nanoparticles as additives in water as yet. In this work, water‐soluble TiO2 nanoparticles were prepared by sol‐gel method and characterized with transmission electron microscopy and selected area electron diffraction. The tribological properties as additives in water were investigated by SRV and the surface analysis by scanning electron microscope and X‐ray photon electron spectroscope.

Findings

TiO2 nanoparticles modified with polyethylene glycol have uniform size about 10 nm and easily dissolve in water. The tribological experiments showed TiO2 nanoparticles exhibit excellent friction‐reducing and antiwear properties.

Research limitations/implications

The paper is restricted to only TiO2 nanoparticles. Some other water‐soluble nanoparticles also should be prepared and their tribological properties investigated.

Practical implications

Water‐soluble TiO2 nanoparticles could be used as water additives and improve the tribological properties.

Originality/value

This paper emphasises that the water‐soluble nanoparticles are prepared and could be used as water additives.

Details

Industrial Lubrication and Tribology, vol. 62 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 25 September 2009

Ming Zhang, Xiaobo Wang, Weimin Liu and Xisheng Fu

The purpose of this paper is to study the tribological performance and anti‐wear mechanism of Cu nanoparticles as lubricating oil additives.

1205

Abstract

Purpose

The purpose of this paper is to study the tribological performance and anti‐wear mechanism of Cu nanoparticles as lubricating oil additives.

Design/methodology/approach

An end‐face wear testing apparatus is used to measure the tribological properties of Cu nanoparticles as lubricating oil additives and using a commercial SJ 15W/40 gasoline engine oil for comparison. Electrical contact resistance (ECR) is measured on a universal nano and micro tester‐2 tribometer to detect the formation of tribo‐film generated by Cu nanoparticulate additive. The worn steel surfaces are investigated by scanning electron microscope (SEM), energy dispersive spectra (EDS) and X‐ray photoelectron spectroscopy (XPS).

Findings

The results show that Cu nanoparticles used as an oil additive can improve the anti‐wear and friction‐reduction performance of SJ 15W/40 gasoline engine oil remarkably. The results of SEM, EDS and XPS show that a deposit film containing metallic copper can form on the worn surface, which has a film thickness of about 120 nm.

Originality/value

This investigation establishes a baseline of Cu nanoparticles used as lubricating oil additives under face‐to‐face contact work conditions. Thus, the results are reliable and can be very useful for further applications of Cu nanoparticle additives in industry.

Details

Industrial Lubrication and Tribology, vol. 61 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 14 June 2013

Ming Zhang, Xiaobo Wang and Weimin Liu

The purpose of this paper is to study the influences of test conditions to the tribological behavior of LaF3 nanoparticles as an additive to a polyalphaolefin (PAO).

286

Abstract

Purpose

The purpose of this paper is to study the influences of test conditions to the tribological behavior of LaF3 nanoparticles as an additive to a polyalphaolefin (PAO).

Design/methodology/approach

An Optimol‐SRV4 oscillating friction and wear tester (SRV) were used to investigate the tribological properties of LaF3 nanoparticles as an additive in a polyalphaolefin (PAO). The 3‐D morphologies and wear loss volume of the worn scar were measured using a surface profilometer. The chemical state and the intensity of La and F elements on worn surface after friction test was investigated with X‐ray photoelectron spectroscopy to interpret the possible mechanisms of friction‐reduction and anti‐wear with LaF3 nanoparticles.

Findings

The experimental results show that LaF3 nanoparticles added to PAO exhibit excellent load‐carrying capacity, anti‐wear and friction‐reduction properties. LaF3 nanoparticles deposited on the worn surface under lower test temperature during the friction test, and higher applied load, higher test frequency and longer test duration are propitious to the deposition of LaF3 nanoparticles accumulated on the rubbing surface. Under higher temperature, a complicated tribo‐chemical reaction occurred during the friction process, the tribo‐chemical reaction product of La2O3 deposit on worn surface, which also exhibits good lubricating performance.

Originality/value

This paper investigates the tribological properties of LaF3 nanoparticles as green oil additive in poly‐alpha‐olefin (PAO) under variable temperature, applied load, sliding speed and sliding duration. The results could be very helpful for the further applications of LaF3 nanoparticles additives in industry.

Details

Industrial Lubrication and Tribology, vol. 65 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 21 September 2012

Xianbing Ji, Yinxia Chen, Xiaobo Wang and Weimin Liu

The purpose of this paper is to study the tribological performance of tri(hydroxymethyl)propane esters containing boron and nitrogen as lubricant additives in rapeseed oil.

259

Abstract

Purpose

The purpose of this paper is to study the tribological performance of tri(hydroxymethyl)propane esters containing boron and nitrogen as lubricant additives in rapeseed oil.

Design/methodology/approach

Thermal degradation tests were performed to analyze their thermal stability using a thermo‐gravimetric analyzer. Two four‐ball testers were used to measure the tribological properties of tri(hydroxymethyl)propane esters containing boron and nitrogen as lubricant additives in rapeseed oil. The worn surfaces of steel balls were investigated by scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS).

Findings

The results show that the tri(hydroxymethyl)propane esters containing boron and nitrogen have excellent thermal stability, good antiwear performance, improve the load‐carrying capacity, and possess friction‐reducing behavior especially at 98 N when they are used as additives in rapeseed oil. The results of XPS show that the adsorption and tribochemical reactions have been occurred to form a complex boundary lubrication film.

Originality/value

The paper illustrates two novel tri(hydroxymethyl)propane esters which contain B and N elements used as additives in rapeseed oil. The results are useful for further applications in advanced environment friendly lubricating oils and additives.

Details

Industrial Lubrication and Tribology, vol. 64 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 8 June 2012

Jiang Wu, Xiaobo Wang, Xianghui Zhao, Chunbao Zhang and Bo Gao

The purpose of this paper is to explore an application of computer‐aided design and manufacture (CAD/CAM) to a process of electronically surveying a scanned dental cast as a prior…

2107

Abstract

Purpose

The purpose of this paper is to explore an application of computer‐aided design and manufacture (CAD/CAM) to a process of electronically surveying a scanned dental cast as a prior stage to producing a sacrificial pattern for a removable partial denture (RPD) metal alloy framework.

Design/methodology/approach

With the introduction of laser scan technology and commercial reverse engineering software, a standard plaster maxillary dental cast with dentition defect was successfully scanned and created as a STL‐formatted digital cast. With the software, the unwanted undercuts were eliminated based on the desired path of insertion. Parts of the RPD framework were then successfully custom‐designed and combined as a whole.

Findings

A sacrificial pattern was produced by rapid prototyping (RP) method and finally casted with chromium cobalt alloy. With suitable finishing process, both the sacrificial pattern and the casted framework fitted the cast well.

Originality/value

The research indicated the feasibility of creating a library of RPD framework components. It is believed that, in the future, with the advance of the techniques, a totally new platform can be developed for the design and fabrication of custom‐fit RPD framework based on the CAD/CAM/RP system.

Details

Rapid Prototyping Journal, vol. 18 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 8 April 2014

Gaiqing Zhao, Qin Zhao, Xiaobo Wang and Weimin Liu

The purpose of this paper is to study a novel Mannich adduct of benztriazole-containing diphenylamine (coded as BD) and its anti-oxidation properties as an additive in two typical…

153

Abstract

Purpose

The purpose of this paper is to study a novel Mannich adduct of benztriazole-containing diphenylamine (coded as BD) and its anti-oxidation properties as an additive in two typical synthetic ester-based oils.

Design/methodology/approach

The anti-oxidation properties in two typical synthetic ester-based oils were evaluated in detail, using rotating pressure vessel oxidation test. The tribological properties of BD in synthetic ester-based oil (A51) were also tested with Optimal SRV-I oscillating friction and wear tester at atmosphere.

Findings

The results of tests demonstrated that the novel BD compound is, indeed, a high-performance anti-oxidation additive that was able to remarkably improve the oxidation stability of synthetic ester-based oils, when it was added at only 0.5 per cent concentration and compared with the base oils containing 0.5 per cent of the commercial available antioxidant additives such as 2, 6-di-tert-butyl-4-methylphenol and octyl-butyl diphenylamine. A plausible mechanism of exceptional synergistic anti-oxidation was proposed.

Originality/value

This paper first investigated the anti-oxidation properties and mechanisms of the compound with the structure of BD, which can be very useful and would promote the application of BD antioxidant in the lubricant industry.

Details

Industrial Lubrication and Tribology, vol. 66 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

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