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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.

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.

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.

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.

This paper aims to synthesize a novel alkanolamine borate and explore the performance of as a copper wire drawing oil.

In this paper, a copper wire drawing oil (CU-KL) was formulated by using a novel alkanolamine borate, naphthenic base oil, fatty alcohol polyoxyethylene ether and palm oil. The tribological performance of CU-KL and commercial copper wire drawing oils (CU-DRB and CU-8010) was investigated

Under applied loads of 5 N-15 N, the average friction coefficient of CU-KL was 29.4%, 5.4% and 25.3% lower than that of CU-DRB, respectively. At sliding speed of 1000–5000 rpm, the average friction coefficient of CU-KL was reduced by 14.3%, 6% and 10.3% compared with CU-DRB, respectively. Through scanning electron microscope and energy dispersive spectrometry, CU-KL can form B-containing compound at the contact interface, which could synergistically enhance the lubrication effect and improve the wear resistance.

The properties of CU-KL under different test condition were studied, and the findings are of great significance for the application of alkanolamine borate in copper wire drawing oil.

The piston ring-cylinder liner pair is one of the most important tribological systems of an internal combustion engine. The friction loss of the piston ring-cylinder liner pair accounts for the largest portion of total efficiency losses. Therefore, improving the tribological system design of the piston ring-cylinder liner pair can reduce friction losses and bring tremendous economic benefits to society. This paper aims use surface texturing, which is proving to be an effective method, for improving the tribological performance of sliding surfaces.

In this paper, an experimental study using a pin-on-disk tribometer was carried out to evaluate the effects of surface texturing on friction reduction of piston rings under various loads and sliding velocities. Rectangular- and circular-shaped textures with different depths and area densities were produced by a Femtosecond laser. Comparison experiments were conducted with un-textured rings.

The results indicate that the friction performance of the ring surface was significantly improved by surface texturing, and the running-in stage was also shortened. More specifically, it was found that the rectangular-shaped texture had a better effect on friction reduction than the circular-shaped texture. Results also indicate that an optimum texture density existed for the rectangular-shaped texture. Additionally, it was observed that the average friction coefficient reduction of the textured ring decreased with increasing load and increased with increasing sliding velocity.

Consequently, these findings provide a more in-depth understanding of the relationship between micro-textures and tribological properties of piston rings in lubricating sliding.

This paper aims to investigate the effect of laser surface texturing on the tribological performance of Ti-6Al-4V disks sliding against Si3N4 balls under hydroxyethyl-cellulose water-based lubrication. The friction coefficients and wear losses of textured and untextured disks were measured and compared. The results indicate that the texture patterns can lead to reduction of friction and wear in the condition of water-based lubrication.

Solutions of hydroxyethyl cellulose were used as water-based lubricants. To find the optimal laser texturing parameters for the best performance enhancement, three line-like patterns were fabricated onto the disks and three machining parameters were used for each type of pattern. Tribological tests were conducted in rotation sliding with ball-on-disk contact configuration on UMT-2.

A higher density of texture lines leads to a larger friction and wear reduction. Compared with untextured disks, the friction coefficient is reduced from 0.043 to 0.028 for textured disks. Some unworn parts were detected in the contact region of the balls against textured disks, which were not found on the balls against untextured disks. The worn surfaces indicated that periodic geometry of the contact track was rebuilt during run-in period, which was beneficial for the formation of lubricant films.

In this work, laser surface texturing was used to reduce the friction and wear of Ti-6Al-4V specimens in water-based lubrication, which can be used to improve the tribological performance of Ti-6Al-4V components in mechanical equipment.

This study aims to clarify the influence mechanism of polishing solution type on the glazing evolution of fixed abrasive pad under different interfacial pressure conditions.

The tribological experiments were carried out on the friction and wear machinery with W3-5 diamond fixed abrasive pad and quartz glass workpiece under three polishing solution types of five pressure conditions. The changes of surface morphology, porosity and hardness of fixed abrasive pad were detected by white light interferometer, optical microscope and shore hardness tester.

The results showed that the glazed phenomenon of fixed abrasive pad is occurred after a certain time, which is more obvious with the increasing of interfacial pressures. The polishing solution type has a significant effect on the glazing time, although the glazed phenomenon is inevitable. The mechanism of it is that the micro-convex peaks on the surface of the fixed abrasive pad are easily wear, and the pores are blocked by the accumulation of waste debris generated during the experiment process. Thus, a smooth and high-density hard layer is formed on the surface of the fixed abrasive pad which induces the decreasing of the friction coefficient and surface roughness value. For selected polishing solution types, the wear rate of micro-convex peaks is different due to the corrosion action difference with polishing pad surface.

The main contribution of this work is to provide a new investigating method for further understanding the glazing evolution mechanism of fixed abrasive pad.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0257/

Chemical mechanical polishing (CMP) has attracted much attention recently because of its importance as a nano-scale finishing process for high value-added large components that are used in the aerospace industry. The paper aims to discuss these issues.

The characteristics of aluminum nanoparticles slurry including oxidizer, oxidizer contents, abrasive contents, slurry flow rate, and polishing time on aluminum nanoparticles CMP performance, including material removal amount and surface morphology were studied.

Experimental results indicate that the CMP performance depends strongly on the oxidizer, oxidizer contents, and abrasive contents. Surface polished by slurries that contain nano-Al abrasives had a lower surface average roughness (Ra), lower topographical variations and less scratching. The material removal amount and the Ra were 124 and 7.61 nm with appropriate values of the process parameters of the oxidizer, oxidizer content, abrasive content, slurry flow rate and polishing time which were H₂O₂, 2 wt.%, 1 wt.%, 10 ml/min, 5 min, respectively.

Based on SEM determinations of the process parameters for the polishing of the surfaces, the CMP mechanism was deduced preliminarily.

The purpose of this paper is to investigate the effects of abrasive contents, oxidizer contents, slurry flow rate and polishing time in achieving a mirror-like finish on polished surfaces. Chemical mechanical polishing (CMP) is now widely used in the aerospace industry for global planarization of large, high value-added components.

Optimal parameters are applied in experimental trials performed to investigate the effects of abrasive contents, oxidizer contents, slurry flow rate and polishing time in achieving a mirror-like finish on polished surfaces. Taguchi design experiments are performed to optimize the parameters of CMP performed in steel specimens.

Their optimization parameters were found out; the surface scratch, polishing fog and remaining particles were reduced; and the flatness of the steel substrate was guaranteed. The average roughness (Ra) of the surface was reduced to 6.7 nm under the following process parameters: abrasive content of 2 weight per cent, oxidizer content of 2 weight per cent, slurry flow rate of 100 ml/min and polishing time of 20 min.

To meet the final process requirements, the CMP process must provide a good planarity, precise selectivity and a defect-free surface. Surface planarization of components used to fabricate aerospace devices is achieved by CMP process, which enables global planarization by combining chemical and mechanical interactions.

This paper aims to investigate the effects of plasma nitriding and Ti-C:H coating deposition on AISI 316L and to find the best tribological performance of various specimens.

An experimental investigation is performed into the effects of plasma nitriding and Ti-C:H sputtering on the tribological properties of AISI 316L biomedical stainless steel. Five samples are prepared, namely, original AISI 316L stainless steel (code: 316L), nitrided 316L (code: N316), 316L and N316 sputtered with Ti-C:H (codes: D316 and DN316, respectively) and polished N316 sputtered with Ti-C:H (DN316s). The microstructure, mechanical properties and coating adhesion strength of the various samples are investigated and compared. The tribological properties of the samples are then evaluated by means of reciprocating wear tests performed in 8.9 Wt.% NaCl solution against three different counterbodies, namely, a 316L ball, Ti₆Al₄V ball and Si₃N₄ ball.

It is shown that plasma nitriding followed by Ti-C:H deposition (DN316s) improves the tribological properties of AISI 316L; the sample provides the best tribological performance of the various specimens and has a wear rate approximately 156 times lower than that of the original 316L substrate.

The results suggest that nitriding followed by polishing and Ti-C:H sputtering provides an effective means of improving the service life of AISI 316L biomedical implants.

The wear properties of tribo‐materials are strongly influenced by the use of lubricants and their additives. The presence of additive in the lubricating oil causes changes in the material surface characteristics by the formation of protective boundary films which result in increased wear resistance of the mating surfaces. In this investigation, wear tests for a segmented piston ring‐plate pair and a ball‐plate pair were carried out using a modified universal wear and friction machine with three different percentages of palm oil methyl ester (POME) added to a mineral oil lubricant. The plain mineral‐based lube oil was also used for comparison purposes. Experimental results show that the activity of POME on the metal surface is quite remarkable when added to a mineral‐based lubricant. Wear of piston ring and ball bearing materials took place by abrasive, corrosive and/or oxidative mechanisms with different concentrations of POME in lubricants. The surface characteristics shown by SEM and EDAX and related phenomena are discussed in this paper.

The purpose of this paper is to provide a review of finishing robot technology and its applications.

The paper initially considers the development of automated finishing technologies and then discusses robotic systems. The uses of robotic finishing are illustrated through reference to a range of applications and case histories and a final section summarises the key benefits of the technology.

The paper shows that robotic finishing is being adopted by a range of industries including the aerospace, automotive, medical and household goods sectors. The technology has been shown to yield significant benefits, notably improved productivity, cost reductions, more consistent quality and reduced reject levels.

The paper provides a useful insight into robotic finishing and illustrates the key applications and benefits of the technology.