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The purpose of this paper is to investigate the tribological properties of a textured lubricating wear-resistant coating modified by nano-SiC at a high temperature. Its aim is to explore the influence of a new composite method on the organisation and structure of sprayed coatings as well as the evolution rules governing their high-temperature tribological properties.

A KF301/WS2 lubricating, wear-resisting, coating was prepared on matrix material GCr15 by applying supersonic plasma spraying technology. On the basis of this sample, using nano-SiC particles as a filler, the KF301/WS2 nano-modified coating with its round, pit-type texture was prepared by laser re-melting technology and a surface texturing technique. Two kinds of coating micro-organisations and structures were examined by scanning electron microscopy, and the tribological properties of both the modified and conventional coatings were studied at a high temperature.

Results showed that nano-particles could effectively improve the coating micro-structure, and make the structure denser and more uniform, thus significantly increasing the wear resistance of the coating. When the friction and wear processes were stable, the friction coefficient decreased by 13 per cent, while the wear loss decreased by 45.9 per cent.

This research concentrating on the study of the process and performance of coatings doped with nano-particles by laser re-melting incorporating simultaneous surface texturing, and studies of their high-temperature tribological properties. That is because applying nano-particle modification technology to the development of wear-resistant coatings, and by applying the nano-particles to such coatings by thermal spraying technology, they can achieve a modification of the coating which makes the structure denser and more uniform.

As a high-performance engineering plastic, polyimide (PI) is widely used in the aerospace, electronics and automotive industries. This paper aims to review the latest progress in the tribological properties of PI-based composites, especially the effects of nanofiller selection, composite structure design and material modification on the tribological and mechanical properties of PI-matrix composites.

The preparation technology of PI and its composites is introduced and the effects of carbon nanotubes (CNTs), carbon fibers (CFs), graphene and its derivatives on the mechanical and tribological properties of PI-based composites are discussed. The effects of different nanofillers on tensile strength, tensile modulus, coefficient of friction and wear rate of PI-based composites are compared.

CNTs can serve as the strengthening and lubricating phase of PI, whereas CFs can significantly enhance the mechanical properties of the matrix. Two-dimensional graphene and its derivatives have a high modulus of elasticity and self-lubricating properties, making them ideal nanofillers to improve the lubrication performance of PI. In addition, copolymerization can improve the fracture toughness and impact resistance of PI, thereby enhancing its mechanical properties.

The mechanical and tribological properties of PI matrix composites vary depending on the nanofiller. Compared with nanofibers and nanoparticles, layered reinforcements can better improve the friction properties of PI composites. The synergistic effect of different composite fillers will become an important research system in the field of tribology in the future.

This paper aims to introduce a high-temperature grease design method assisted by back propagation neural network (BPNN) and verify its application value.

First, the grease data sets were built by sorting out the base data of greases in a large number of literatures and textbooks. Second, the BPNN model was built, trained and tested. Then, the optimized BPNN model was used to search the unknown data space and find the composition of greases with excellent high-temperature performance. Finally, a grease was prepared according to the selected composition predicted by the model and the high-temperature physicochemical performance, high-temperature stability and tribological properties under different friction conditions were investigated.

Through high temperature tribology experiments, thermal gravimetric analysis and differential scanning calorimetry experiments, it is proved that the high temperature grease prepared based on BPNN has good high-temperature performance.

To the best of the authors’ knowledge, a new method of designing and exploring high-temperature greases is successfully proposed, which is useful and important for the industrial applications.

The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS₂ as the lubricating phase, which provides a theoretical basis for subsequent research on high-performance copper-based self-lubricating materials.

Friction tests were performed at a speed of 100 r/min, a load of 10 N, a friction radius of 5 mm and a sliding speed of 30 min. Friction experiments were carried out at RT-500°C. The phase composition of the samples was characterized by X-ray diffraction of Cu Ka radiation, and the microstructure, morphology and elemental distribution were characterized by scanning electron microscopy and energy dispersive spectroscopy. Reactants and valences formed during the wear process were analyzed by X-ray photoelectron spectroscopy.

The addition of MoS₂ can effectively improve friction-reducing and anti-wear action of the matrix, which is beneficial to form a lubricating film on the sliding track. After analyzing different changing mechanism of the sliding tracks, the oxides and sulfides of MoS₂, MoO₂, Cu₂O, CuO and Ni(OH)₂ were detected to form a synergetic lubricating film on the sliding track, which is responsible for the excellent tribological properties from room to elevated temperature.

For self-lubrication Cu–Sn–Ni–MoS₂ material in engineering field, there are still few available references on high-temperature application.

This paper provides a theoretical basis for the following research on copper-based self-lubricating materials with high performance.

With this statement, the authors hereby certify that the manuscript is the results of their own effort and ability. They have indicated all quotes, citations and references. Furthermore, the authors have not submitted any essay, paper or thesis with similar content elsewhere. No conflict of interest exits in the submission of this manuscript.

To improve the high-temperature wear properties of the SiCp/A359 composite, foamed iron-reinforced SiCp/A359 composite (A359–SiCp/Fe) is prepared. The purpose of this study is to investigate the tribological behavior and mechanism of the A359–SiCp/Fe composites at different temperatures (100–500 °C) and loads (7 N, 10 N and 12 N).

The A359–SiCp/Fe composite was fabricated by vacuum-assisted infiltration. The dry sliding tribological behaviors of A359–SiCp/Fe composite were investigated using the ball-on-disc-type tribometer. The worn surface and wear morphology of the longitudinal section were examined using field emission scanning electron microscopy and metallographic microscope.

The critical transition temperature for severe wear in A359–SiCp/Fe composite was 50–100 °C higher than in SiCp/A359 composite. Foamed iron prevents exfoliation cracks from penetrating deeper into the matrix. The friction coefficient stability of the A359–SiCp/Fe composite was higher than the unreinforced composite at elevated temperatures. With the increase in temperature, the friction-affected layer was severely worn, and the wear mechanism transferred from abrasion and delamination to oxidation and plastic flow, respectively.

The preparation procedure for aluminum matrix composites reinforced with foamed metal has been less reported, and the research on the tribological behavior and mechanism of A359–SiCp/Fe composite at various temperatures is insufficient. The foamed iron structure considerably enhances the wear properties of SiCp/A359 composite in elevated temperature conditions.

This study aims to investigate the high-temperature wear behavior of the TiN- and AlTiN/TiSiN-coated WC materials.

The coating process was carried out using the physical vapor deposition (PVD) method. Wear tests were performed by a ball-on-disc wear device with a high-temperature wear module. In microstructural investigation of the materials, it was benefited from traditional characterization methods such as, SEM, EDX analysis and microhardness measurement.

The best wear performance was obtained with AlTiN/TiSiN-coated WC materials at all loads and temperatures, followed by TiN-coated and uncoated WC samples. An important wear was not observed on the samples tested at room temperature tests. It was found that the temperature increase is an effective parameter on the decrease of the wear resistance of the samples. In addition, it was seen that the increasing load and temperature change the wear mechanism on the uncoated WC sample. The wear mechanisms observed at high temperatures were delamination and oxidation for the WC, fatigue for AlTiN/TiSiN-coated WC and micro-scratch and micro-spalling for TiN-coated WC.

The results of the experimental studies demonstrated that hard coatings improving wear resistance of WC.

The purpose of this study is to investigate the effects of load and rotation speed on dry sliding of silicon nitride, including a series of tribological behaviors (friction coefficient, wear rate, temperature rise, etc.) and wear mechanism. Through the analysis of the above characteristics, the influence law of load and speed on them and the internal relationship between them are determined, and then the best comprehensive performance parameters of silicon nitride full-ceramic spherical plain bearings in dry sliding are predicted, which can provide guidance for the operation condition of silicon nitride full-ceramic spherical plain bearings in dry sliding.

The experimental study of different loads and rotation speeds under dry friction conditions was carried out by the using ball-disk sliding test method.

With the increase of load, the friction coefficient of silicon nitride friction pair and the wear rate of silicon nitride ball decrease continuously. With the increase of rotation speed, the friction coefficient of silicon nitride friction pair first increases and then decreases, and the wear of silicon nitride ball first increases and then decreases. With the increase of load and rotation speed, the wear mechanism eventually changes to adhesive wear.

Because of the low timeliness and inefficiency of bearing experiments, this work adopts a simple ball-disk model to comprehensively explore the influence rules of different conditions, which provides a theoretical basis for the subsequent practical application of silicon nitride full-ceramic spherical plain bearings.

The paper covers work done at Salford University and identifies those aspects of tribology which are important to both the design of metal working machines and to the tool/workpiece interaction. After identifying the important tribological problem areas some examples of possible methods of solution are indicated using the work at Salford University for typical examples. Inevitably the paper identifies many questions to which there are currently very limited answers and thereby indicates the areas for further research. It should however be stressed that the author does not claim to have produced a comprehensive review on tribology in manufacturing engineering. Rather the style of the paper is to question the way forward and in some cases even to propose answers.

The purpose of this paper is to examine mechanical and metallurgical properties of AlTiN coating HSS materials in detail.

In this study, high-speed steel (HSS) parts were processed by the way of machining and were coated with AlTiN on physical vapour deposition (PVD) workbench at approximately 650°C for 4 h. Tensile strength, fatigue strength and hardness tests for AlTiN coated HSS samples were performed. Samples were also analyzed by energy dispersive X-ray analysis (EDS), X-ray diffraction (XRD) and scanning electron microscope (SEM). The results were compared with uncoated HSS components.

It was found that an amorphous aluminium-oxide layer emerges on surface of parts by AlTiN coating. This layer prevents further oxide formations. The coating thickness of AlTiN-coated sample is between 1,530 and 1,558 μm. Compared to uncoated HSS, AlTiN coated HSS gives higher performance.

It would be interesting to search different coatings for cutting tools. It could be the good idea for future work concentrated wear properties on tool materials using different coatings.

This paper provides information on mechanical and metallurgical behaviour of AlTiN coated HSS materials and offers practical help for the researchers and scientists working in the coating area.

The purpose of this study is to determine the tribological behavior and wear mechanism of a polytetrafluoroethylene (PTFE)/polyester (PET) fabric composite for application as a self-lubricating liner suitable for high-speed and low-load friction conditions.

The effects of different loads and sliding speeds on the friction coefficients and wear characteristics of the composite were studied using reciprocating friction tests. Scanning electron microscopy, extended depth-of-field microscopy, and energy-dispersive X-ray spectrometry was used to analyze the worn surface morphology, wear depth and elemental content of the lubrication films, respectively.

The friction coefficient curves of the composites presented a long-term steady wear stage under different sliding conditions. With increasing sliding speed, the friction coefficient and wear depth of the composite slowly increased. The film-forming mechanism of the composite revealed that the PTFE/PET ply yarn on the composite surface formed complete PTFE lubrication films at the initial sliding stage.

The PTFE/PET fabric composite maintained good friction stability and high-speed adaptability, which demonstrates that the composite has broad application prospects as a highly reliable self-lubricating bearing liner with a long lifespan.