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Article
Publication date: 12 July 2022

Meng Fanjing, Minghua Pang and Lijie Ma

Carbon steel has a high application rate in modern industry, but this type of steel has the defect of high wear. This study aims to improve the surface friction and wear…

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Abstract

Purpose

Carbon steel has a high application rate in modern industry, but this type of steel has the defect of high wear. This study aims to improve the surface friction and wear performance of carbon steel under such working conditions.

Design/methodology/approach

In this study, a dry film lubricant based on graphite powder was prepared by the ultrasonic dispersion method, and deposited on the surface of carbon steel specimens by the simple pressure spraying technology. At the same time, molybdenum disulfide and polytetrafluoroethylene dry film lubricants were developed by the same method, and the comparative experimental study on friction and wear was carried out in the end-face friction tester.

Findings

The results show that the deposition effect of graphite and molybdenum disulfide dry film lubricants on the surface of carbon steel is obviously better than that of polytetrafluoroethylene dry film lubricant. Compared with molybdenum disulfide and polytetrafluoroethylene dry film lubricant, graphite dry film lubricant has the best friction and wear performance on the surface of carbon steel. The working life of carbon steel specimens sprayed with graphite dry film lubricant decreases with the increase of pressure load and rotation speed. The combination of load and sliding speed will accelerate the transition of the coating to a stable direction. In addition, the micro lubricant particles formed in the wear process will form particle flow lubrication, and the appropriate addition of particle powder of the same material will also prolong the normal antifriction time of the lubricant.

Originality/value

These findings developed a dry film lubricant that can effectively improve the friction and wear properties of carbon steel surface.

Details

Industrial Lubrication and Tribology, vol. 74 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Open Access
Article
Publication date: 15 November 2022

Liyao Song, Bai Chen, Bo Li, Rupeng Zhu and Dan Wang

The supercritical design of tail rotor drive shaft has attracted more attention in helicopter design due to its high power–weight ratio and low maintenance cost. However, there…

Abstract

Purpose

The supercritical design of tail rotor drive shaft has attracted more attention in helicopter design due to its high power–weight ratio and low maintenance cost. However, there exists excessive vibration when the shaft passes through the critical frequency. Dry friction damper is the equipment applied to the drive shaft to suppress the excessive vibration. In order to figure out the damping mechanism of the dry friction damper and improve the damping efficiency, the dynamic model of the shaft/damper system is established based on the Jeffcott rotor model.

Design/methodology/approach

The typical frequency response of the system is studied through bifurcation diagrams, amplitude-frequency characteristic curves and waterfall frequency response spectrum. The typical transient responses under frequency sweeps are also obtained.

Findings

The results show that the response of the system changes from periodic no-rub motion to quasi-periodic rub-impact motion, and then to synchronous full annular rub-impact, and finally, back to periodic no-rub motion. The slip of the rub-impact ring improves the stability of the system. Besides, the effects of the system parameters including critical dry friction force, rub-impact friction coefficient, initial clearance on the stability and the vibration damping capacity are studied. It is observed that the stability changes significantly varying the three parameters respectively. The vibration damping capacity is mainly affected by the critical dry friction force and the initial clearance.

Originality/value

Presented results provide guidance for the design of the dry friction damper.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. 3 no. 2
Type: Research Article
ISSN: 2633-6596

Keywords

Article
Publication date: 4 March 2014

Qiulin Niu, Xiaohu Zheng, Ming Chen and Weiwei Ming

Titanium alloy has the excellent performance and been widely utilized in aeroengine and airframe manufacture. However, improving the understanding of all aspects of titanium alloy…

Abstract

Purpose

Titanium alloy has the excellent performance and been widely utilized in aeroengine and airframe manufacture. However, improving the understanding of all aspects of titanium alloy is necessary. The purpose of this paper is to investigate the tribological properties of two typical titanium alloys against tungsten carbide under dry friction.

Design/methodology/approach

Reciprocating ball-disc friction tests were carried out at room temperature in different loading without lubricant to investigate the friction properties of TA19/WC-Co and TC18/WC-Co friction pairs. The influence of the load on the friction coefficient and friction force was analyzed. The worn surfaces of TA19 and TC18 specimens were observed by the digital microscopy and scanning electron microscopy (SEM). And the wear mechanism was discussed.

Findings

The results show that the friction coefficients decreased with the increase in the normal load. However, the reduction in the friction coefficient for the TC18 alloy was less than that for the TA19 alloy. The dynamic friction forces with time were not quite coincident with the variation trend of the friction coefficients during the sliding friction. The results observed by the SEM and EDS revealed that several grooving were the main type of frictional wear causing the surfaces of the TA19 and TC18 alloys.

Originality/value

It is shown in the paper that the tribological property of TA19 alloy was better than that of TC18 when sliding against tungsten carbide under the dry friction conditions. The main types of damage to the TA19/WC-Co friction pair were the ploughing, the delamination fatigue associate with abrasive wear and some diffusive wear. The ploughing and abrasion were the main wear mechanisms for the surface of TC18 alloy.

Details

Industrial Lubrication and Tribology, vol. 66 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 4 January 2019

Guo-yuan Zhang, Jia-qi Dang, Wei-gang Zhao and Xiu-tian Yan

The serious friction and wear problem occurs on the mechanical seal’s faces during the start-up stage of the high-speed turbopump for a liquid rocket engine. This paper aims to…

332

Abstract

Purpose

The serious friction and wear problem occurs on the mechanical seal’s faces during the start-up stage of the high-speed turbopump for a liquid rocket engine. This paper aims to propose a kind of thick metal alloy coatings on the surface of the seal’s rotor so as reduce the friction and wear.

Design/methodology/approach

With the pin-disk (the graphite pin and the disk with the metal coating) tribology-tester, the tribological behaviors of four metal coatings are investigated. The special friction coefficients under the dry friction, boundary friction and different temperatures of water-lubricated conditions were obtained.

Findings

The test results show that the thick metal coating has a good performance of the wear resistance and friction reduction; and the friction coefficients of a Sn-Sb-Cu coating under the dry friction and water-lubricated conditions are 0.377 and 0.043, respectively, and the corresponding mass wear volumes are only 2.74 and 0.81 mg, respectively.

Originality/value

The thick metal coating scheme for the mechanical seal’s faces might lend itself to the harsh working conditions of the low-viscosity liquid rocket engine.

Details

Industrial Lubrication and Tribology, vol. 71 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 13 February 2009

Alejandro B. Engel and Paul H. Stiebitz

The purpose of this paper is to provide a study of inertial propulsion.

Abstract

Purpose

The purpose of this paper is to provide a study of inertial propulsion.

Design/methodology/approach

In this paper, the theory of inertial propulsion under dry friction and under viscous friction is developed.

Findings

As inertia propelled devices do not have any external moving parts; the propelling mechanism is completely enclosed inside the device. For inertial propulsion under dry friction, the equations of movement are explicitly derived and provided in closed form, so that such a device can be designed with its parameters computed exactly. For inertial propulsion under viscous friction, on the other hand, there is no closed form for the equations of movement, its dynamics are provided so that a device can be designed using a computer algebra system, as illustrated in the paper.

Originality/value

The paper demonstrates that an inertia propelled device under dry friction moves in the opposite direction than the same device under viscous friction.

Details

Kybernetes, vol. 38 no. 1/2
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 6 December 2020

Srinivasula Reddy I. and Vadivuchezhian Kaliveeran

This paper aims to focus on the effect of normal load, sliding speed and temperature on the coefficient of friction of Al 6061-T6 alloy under dry sliding conditions.

Abstract

Purpose

This paper aims to focus on the effect of normal load, sliding speed and temperature on the coefficient of friction of Al 6061-T6 alloy under dry sliding conditions.

Design/methodology/approach

Dry sliding experiments were conducted using rotary type pin on disk tribometer. Pins with 3 mm radius of contact and circular disks of 165 mm diameter were fabricated to simulate Hertzian contact configuration. Experiments were conducted by applying three different normal loads (1, 1.5 and 2 kg) and three different sliding speeds (1.25, 2 and 3 m/s) at different temperatures [room temperature (31 ± 1 °C), 60 °C, 100 °C and 150 °C].

Findings

Coefficient of friction at end of the first cycle of sliding, stabilized stage, unsteady state and steady state are reported elaborately in this study. Adhesive and abrasive wear mechanisms were observed in the dry sliding of Al 6061- T6 alloy contacts from the microscopic analysis of worn contact surfaces. The coefficient of friction was more influenced by the increase in normal load than the increase in sliding speed and temperature.

Practical implications

The results obtained from this study are significant for the design of aluminium-to-aluminium contacts in aerospace engineering and automobile engineering.

Originality/value

This study reveals the coefficient of friction of aluminium-to-aluminium (Al 6061-T6 alloy) contacts under cylinder on flat contact configuration.

Details

World Journal of Engineering, vol. 18 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 30 November 2022

Sarita Bharti and Senthilvelan Selvaraj

This paper aims to understand the effect of the manufacturing process on the frictional and wear performance of polyamide.

122

Abstract

Purpose

This paper aims to understand the effect of the manufacturing process on the frictional and wear performance of polyamide.

Design/methodology/approach

Pin specimens were manufactured through injection moulding (IM) and selective laser sintering (SLS) manufacturing processes. The friction and wear performance was evaluated using a pin-on-disc configuration under dry and oil-lubricated conditions. The friction coefficient, wear resistance and surface temperature of specimens were measured, and failure morphology analysis was carried out to understand the mechanism.

Findings

SLS material exhibited significantly less friction, wear and surface temperature than IM material under dry conditions. Reduced ductility due to the sintering contributes to reduced friction, wear and heat generation. Under the dry condition, IM material exhibited plastic flow and roll-shaped deformation, whereas SLS material exhibited only local degradation due to its lesser ductility. Lubrication reduced friction and temperature for both SLS and IM materials. The porous nature of the sintered surface absorbed the lubricant and released it while sliding, which is confirmed by the brown-coloured wear track.

Originality/value

The study provides valuable input to the designers on the sliding contact performance of commonly adopted two different manufacturing processes of polymers; IM and SLS manufacturing.

Details

Industrial Lubrication and Tribology, vol. 75 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Abstract

Details

The Handbook of Road Safety Measures
Type: Book
ISBN: 978-1-84855-250-0

Article
Publication date: 16 October 2018

Guotao Zhang, Yanguo Yin, Ting Xie, Dan Li, Ming Xu and Congmin Li

This paper aims to obtain high mechanical and good tribological properties of epoxy resin-based coatings under dry friction conditions.

Abstract

Purpose

This paper aims to obtain high mechanical and good tribological properties of epoxy resin-based coatings under dry friction conditions.

Design/methodology/approach

Bonded solid lubricant coatings containing Kevlar fibres were prepared by a spraying method. The friction and wear properties of the coatings were experimentally investigated with a face-to-face tribometre under dry friction conditions. Scanning electron microscopy, energy dispersive X-ray spectroscopy and 3D laser scanning technologies were used to characterise the tribological properties. The action mechanism of the Kevlar fibres on a solid lubricant transfer film was also analysed.

Findings

Adding Kevlar fibres can significantly improve the wear resistance of the coatings. When the Kevlar fibre content increases, the tribological properties of the coatings improve and then worsen. Superior properties are obtained with 0.03 g of Kevlar fibres. Appropriately increasing the load or speed is beneficial to the removal of the outer epoxy resin and the formation of a lubricant film. During friction, the solid lubricants wrapped in the epoxy resin accumulate on the surface to form a transfer film that shows a good self-lubricating performance. In the later friction stage, fatigue cracks occur on the solid lubricant film but cannot connect to one another because of the high wear resistance and the entanglement of the rod-like Kevlar fibres. Thus, no large-area film falls from the matrix, thereby ensuring the long-term functioning of solid lubricant coatings.

Originality/value

Epoxy resin-based solid lubricant coatings modified by Kevlar fibres were prepared, and their friction and wear properties were investigated. Their tribological mechanisms were also proposed. This work provided a basis for the analysis of the tribological properties and design of bonded solid lubricant coatings containing Kevlar fibres.

Details

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

Keywords

Article
Publication date: 16 February 2022

Meiling Wang, Qin Li, Zhiqiang Huang, Weiji Qian, Xiong Chen, Qiang Li and Tianhua Lai

This study aims to solve the premature failure of the rubber stator due to wear, reduce the frictional resistance moment of the screw pump to solve the problem of a model of…

Abstract

Purpose

This study aims to solve the premature failure of the rubber stator due to wear, reduce the frictional resistance moment of the screw pump to solve the problem of a model of Daqing oilfield screw pump oil recovery system shutdown after the difficult start.

Design/methodology/approach

For the first time, the rotor surface of a screw pump was treated with dot-matrix texture to study the effect of dot matrix texture on the tribological performance of the stator-rotor friction subsets of screw pump. Reciprocating friction tests with different texture morphologies (S-shape, double tongue) and angular parameters (0°, 45° and 90°) were conducted at 10% of the texture area and pump silicone grease.

Findings

When point texture was added to the surface of the rotor sample, the friction coefficient and wear quantity of the sample were lower than those of the surface without texture treatment, and the double tongue 0° combination showed the best tribological properties. At this time, the average coefficient of friction and wear is reduced by 22.8% and 62%, 28.6% and 64.8%.

Originality/value

The introduction of texture can effectively improve the tribological performance of progressive screw pumps, and this paper provides important theoretical and experimental support for the design of progressive screw pumps in practical applications.

Details

Industrial Lubrication and Tribology, vol. 74 no. 8
Type: Research Article
ISSN: 0036-8792

Keywords

1 – 10 of over 3000