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The purpose of this study is to solve the oil drill pipe joints and casing excessive wear problems and to improve the drill pipe joint-casing wear resistance and anti-friction properties.

On the surface of the drill pipe joints using oxyacetylene flame bead weld (BW) wear-resistant welding wire ARNCO-100XT^TM prepares welding layer, high-velocity oxygen fuel (HVOF) Cr₃C₂75-NiCr25 prepares coating and subsonic flame spray and remelt (SFSR) Ni60 prepares coating, then comparing and analyzing the friction and wear of the three types of wear-resistant layers and the casing under the condition of 1.8 g/cm³ mud drilling fluid lubrication. The wear resistance and anti-friction performance of the drill pipe joints were evaluated based on the wear situation, finally revealing its friction and wear mechanisms.

Three types of wear-resistant layers can improve the surface wear resistance of drill pipe joints, the wear-resistant layer and the substrate are well combined and the welding layers and coating are both dense and uniform. The wear resistance of the HVOF-Cr₃C₂75-NiCr25 coating is 10.9 times that of the BW-ARNCO-100XT^TM weld layer, and the wear resistance of the SFSR-Ni60 weld layer is 2.45 times that of the BW-ARNCO-100XT^TM weld layer. The anti-friction properties of SFSR-Ni60 welding layer is the best, followed by HVOF-Cr₃C₂75-NiCr25 coating, and the anti-friction properties of BW-ARNCO-100XT^TM welding layer is the worst among the three.

The research results of this paper have great practical value in the process and material of improving the wear resistance and anti-friction performance of the drill pipe joint casing.

HIGH TEMPERATURE LUBRICATION, in terms of conventional usage, includes typical applications such as the diesel engine, the roll neck bearings of steel rolling mills or the cylinders of steam engines using superheated steam. This was certainly the case immediately prior to the second world war when, for example, Nash and Bowen, refer merely to the influence of high temperature on oil viscosity, the development of acidity and the formation of carbon. At that time King and Jakeman developed a test machine where, at constant pressure, one of the criteria used for oil evaluation was the seizing temperature ; the highest temperature recorded being of the order of 550°F.

Serpentine is usually added into the lubricant oil to form a self-repairing protective layer on worn ferrous surface. But few works have paid close attention to the preparation of composites with the addition of serpentine. In this work, serpentine reinforced Al matrix composites were successfully prepared to be industrial lubrication components. And its fabricating parameters, compressive strength and tribological properties were analyzed.

An MM-W1 three-pin-on-disk apparatus was used to investigate the tribological properties. The worn surface, microstructure and cross-sectional morphologies were characterized by scanning electron microscopy equipped with energy dispersive spectroscopy. The compression test was carried out on a universal testing machine. An X-ray diffractometer was used to investigate the phase constitutions. The decomposition temperature of serpentine powders was investigated by a thermal analyzer, which allows simultaneous differential scanning calorimetry and thermogravimetry. With the help of finite element method model, a diagrammatic model of the self-repairing surface layer was developed to analyze the anti-friction mechanism.

Through evaluating density and Brinell hardness, sintering at 560°C for 3 h are the appropriate parameters for fabricating the composites. Compressive strength was increased by the addition of serpentine. A self-repairing surface layer was formed, reducing the friction coefficient. And a diagrammatic model of the self-repairing surface layer was developed to analyze the anti-friction mechanism.

Serpentine was added in fabricating the Al matrix composites for the first time. Sintering parameters were optimized to make better Al/Si/serpentine composites. Compressive strength was increased by the addition of serpentine. A self-repairing surface layer was formed, reducing the friction coefficient under the dry sliding condition. And a diagrammatic model of the self-repairing surface layer was developed to analyze the anti-friction mechanism. It is hoped to be helpful in further confirming the factors for the formation of the self-repairing surface layer, and in designing a new industrial anti-friction composite used for dry sliding conditions.

The purpose of this paper is to synthesize a microemulsion and investigate its tribological properties as lubricant. Magnesium alloy warm rolling experiments were conducted. Surface morphology was observed and wear form was summarized. The composition of surface residues was analyzed, which sheds light on the lubrication mechanism of microemulsion.

A microemulsion was prepared with a proper amount of oil, surfactant, cosurfactant, water and other additives for magnesium alloy strip warm rolling. Tribological properties, such as maximum non-seizure load (P_B), friction coefficient (μ) and wear scar diameter (D) of the microemulsion were measured and compared with those of emulsion and rolling oil on an MR-10A four-ball tribotester. The extreme pressure anti-wear coefficients (O) were calculated and compared. Warm rolling experiments were carried out on a Ф 170/400 × 300 mm four-high rolling mill at 240°C to compare the finish rolling thickness and surface quality of rolled AZ31B magnesium alloy strip under four lubrication states, namely, no lubrication, rolling oil, microemulsion and emulsion. The surface morphology after warm rolling was observed with confocal laser scanning microscope and scanning electron microscope, respectively. The composition of surface residues was analyzed with energy dispersive spectrometry and X-Ray photoelectron spectroscopy.

Surface morphology indicated that pitting wear, adhesive wear and ploughing wear were three main forms of wear in magnesium alloy warm rolling. Microemulsion had excellent lubrication properties with less residual oil remaining. Two types of adsorption layers formed on magnesium alloy strip surface were responsible for lubrication properties. MgSO₄ and magnesium stearate in the reaction layer played a key role in anti-wear and friction-reduction in warm rolling.

The study is original and gives valuable information on lubrication mechanism of microemulsion in warm rolling of magnesium alloy strips.

This paper aims to coat ternary composite NiBP-graphite films by Dynamic Chemical Plating “DCP” technique with a growth rate of at least 5 μm/h, which makes this technique a worthy candidate for production of composite films. Electroless nickel plating method can be used to deposit nickel–phosphorous and nickel–boron coatings on metals or plastic surface. However, restrictions such as toxicity, short lifetime of the plating-bath and limited plating rate have limited applications of conventional electroless processes.

DCP is an alternative for producing metallic deposits on non-conductive materials and can be considered as a modified electroless coating process. Using a double-nozzle gun, two different solutions containing the precursors are sprayed simultaneously and separately onto the surface. With this technique, NiBP-graphite films are fabricated and their corrosion and tribological properties are investigated.

With a film thickness of 2 μm, tribological analysis confirms that these coatings have favorable anti-friction and anti-wear properties. Corrosion resistance of NiBP-graphite composite films was investigated, and it was found that graphite incorporation significantly enhances corrosion resistance of NiBP films.

DCP is faster and simpler to perform compared to other electroless deposition techniques. Using a double-nozzle gun, metal salt solution and reducing agents are sprayed to the surface, forming a deposit. Previously, coatings such as Cu, Cu-graphite, Cu-PTFE, Ni-B-TiO2, Ni-P, Ni-B-P and Ni-B-Zn with favorable compactness and adherence by DCP were reported. In this paper, the authors report the application of the DCP technique for depositing NiBP-PTFE nanocomposite films.

Nano‐imprint forming (NIF) is a manufacturing technology capable of achieving high resolution, low‐cost and high‐throughput fabrication of fine nano‐scale structures and patterns. The purpose of this paper is to use modelling technologies to simulate key process steps associated with the formation of patterns with sub‐micrometer dimensions and use the results to define design rules for optimal imprint forming process.

The effect of a number of process and pattern‐related parameters on the quality of the fabricated nano‐structures is studied using non‐linear finite element analysis. The deformation process of the formable material during the mould pressing step is modelled using contact analysis with large deformations and temperature dependent hyperelastic material behaviour. Finite element analysis with contact interfaces between the mould and the formable material is utilised to study the formation of mechanical, thermal and friction stresses in the pattern.

The imprint pressure, temperature and the aspect ratio of grooves which define the pattern have significant effect on the quality of the formed structures. The optimal imprint pressure for the studied PMMA is identified. It is found that the degree of the mould pattern fulfilment as function of the imprint pressure is non‐linear. Critical values for thermal mismatch difference in the CTE between the mould and the substrate causing thermally induced stresses during cooling stage are evaluated. Regions of high stresses in the pattern are also identified.

Design rules for minimising the risk of defects such as cracks and shape imperfections commonly observed in NIF‐fabricated nano‐structures are presented. The modelling approach can be used to provide insights into the optimal imprint process control. This can help to establish further the technology as a viable route for fabrication of nano‐scale structures and patterns.

Studies on this topic have shown the remarkable lubricating properties, viz. friction-reducing and anti-wear, of certain nanoparticles. This makes them potential candidates for replacing the lubrication additives currently used in automobile lubricants, especially because the latter is known to be pollutants and less efficient in some specific conditions. This has not gone unnoticed to professionals in the sector, including those commercializing these additives, the oil companies and the car industry, all of whom are following this burgeoning research area with keen interest. All of them are faced with the problem of providing lubricants that meet the needs of the technological evolution of engines while respecting ever-stricter environmental norms.

The impact of copper oxide (CuO) and zinc oxide (ZnO) nanoparticles on the tribological properties of the SAE-40 pure diesel oil is studied in this paper. The two nanoparticles are not oxide or deteriorate with the base oil. The average size of CuO and ZnO nanoparticles is 40 and 20 nm, respectively. Nanoparticle concentrations of 0.1 Wt.%, 0.2 Wt.%, 0.3 Wt.%, 0.4 Wt.% and 0.5 Wt.% are tested using a pin-on-disk tribometer to evaluate their impact on friction and wear. The test is carried out at different loads and rotating speeds of 58.86 N and 300 rpm, 39.24 N and 500 rpm and 78.48 N and 900 rpm at room temperature, respectively.

The obtained results of the nanolubricants are compared with those of pure diesel oil in terms of % improvement in tribological properties. However, it is observed that an increase in the nanoparticle concentrations does not guarantee to enhance the tribological properties. Similarly, increasing the applied load and the rotating speed does not lead to improving the anti-friction and anti-wear properties. The results obtained revealed that the optimal improvements in the anti-friction and anti-wear properties of the pure oil are 69% and 77% when CuO nanoparticle concentrations of 0.3 Wt.% and the ZnO nanoparticle concentrations of 0.1 Wt.% are used, where the applied load and rotating speed are 39.24 N and 500 rpm, respectively. It has also been noticed that the CuO nanolubricants have a significant impact on the anti-friction property compared with ZnO nanolubricants.

All these nanoparticles have been the subject of detailed investigation in this research and many key issues have been tackled, such as the conditions leading to these properties, the lubrication mechanisms coming into play, the influence of parameters such as size, structure and morphology of the nanoparticles on their tribological properties/lubrication mechanisms and the interactions between the particles and the lubricant co-additives. To answer such questions, state-of-the-art characterization techniques are required, often in situ, and sometimes an extremely complex set up. Some of these can even visualize the behavior of a nanoparticle in real time during a tribological test. The research on this topic has given a good understanding of the way these nanoparticles behave, and we can now identify the key parameters to be adjusted when optimizing their lubrication properties.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2022-0234/

This paper aims to use this method to explore a new approach and possible technical optimal design for lubricant formulation.

The component of the developed oil was determined based on the physical and chemical properties of the base oil and the tribological properties. The analytic hierarchy process (ANP) method and SuperDecisions software were used for hydraulic oil modeling and calculation while taking performance index, work circumstance and economy into consideration.

The hydraulic oil formulation can be optimized using the ANP method, where the technical performance, economy and working circumstances of the hydraulic oils were taken into consideration in the evaluation system. The experiment analyzed and scored and screened the hydraulic oil formula in an objective and comprehensive manner.

The experiments showed that the newly developed hydraulic oils could meet the performance requirements for new energy vehicles equipped with hybrid hydraulic engines.

This paper aims to present a study on composite coating films for solid lubrication applied on the surface of bearings and gears, which are exposed to the vacuum vessel of a tokamak fusion experimental device running under ultra-high vacuum conditions. Experimental advanced superconducting tokamak is a tokamak fusion experimental device running under ultra-high vacuum conditions. To avoid polluting the inner vessel environment, solid lubrication has been applied on the surface of bearings and gears, which are exposed to the vacuum.

Anti-friction MoS₂ coatings integrated with Titanium and Carbon have been developed using the multi-target magnetron sputtering deposition technique. This paper presents the comparative testing of tribological properties for three kinds of MoS₂-based coating layers.

Based on the test results, MoS₂-Ti-C coating films are supposed to be the final selection because of the better performance of friction coefficient and lubrication longevity.

Finally, the detailed information has been characterized for the hybrid coatings, which can provide some references for applications of solid lubrications under similar conditions of high vacuum and temperature.

Due to the environmental issues caused by petroleum lubricants used in lubrication, the concept of creating various bio-lubricants requires research globally. Thus, this study aims to develop, characterize and test the base ficus carica oil (fig oil) for its ethylene vinyl acetate copolymer (EVA) and sodium dodecylbenzene sulfonate (SDBS) content.

The sample characterization was done using the Fourier transmission infrared spectrum, whereas the morphologies of the EVA, SDBS particles and lubricated surfaces were carried out under scanning electron microscope equipment. To ensure the homogeneity of the solution (base oil and additives), the formulations were subjected to the sonication process. The anti-friction and anti-wear properties of EVA and SDBS particles as lubricant additives were investigated using a ball on a flat high-frequency reciprocating rig tribo-tester.

According to the findings, the base oil’s anti-friction and anti-wear capabilities can be greatly enhanced by the additions. revealed that the best results were obtained when 1.2% EVA + 2% SDBS was applied for the examination of wear (597.8 µm) and friction coefficient (0.106). Commercial references were used, nevertheless, and the results were excellent. This is because the particles in the contact area during lubrication have strong solubility and quickly penetrate the contact zone. The lubricating mechanisms were explained by a tribological model of the EVA + SDBS and SDBS particles.

The coefficient of friction and wear reduction caused by the use of the additives will certainly enhance system performance and protect the machine components from excessive wear that could cause damage or failure.

The originality and uniqueness of this work are officially affirmed by the authors. The authors’ autonomous and original contribution to the development of sustainable lubrication is represented in this work. To the best of the authors’ knowledge, no other study has been published or made publicly available that duplicates the precise scope and goals of our research, and this conclusion is based on a thorough literature assessment.