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This study aims to investigate the effects of graphite-MoS₂ composite solid lubricant on the tribological properties of copper-based bearing materials under dry conditions.

The mixture of Graphite-MoS₂ was inlaid in ZQSn6-6–3 tin bronze and ZQAl9-4 aluminum bronze matrix. These copper-embedded self-lubricating bearing materials were considered in friction pairs with 2Cr13 stainless steel, and their tribological properties were studied by using an MM200 wear test machine.

The results show that the friction coefficients and wear rates of copper-embedded self-lubricating bearing materials are lower than those of the ordinary copper-based bearing materials. The wear performance of the tin bronze inlaid self-lubricating bearing material is better than that of the aluminum bronze inlaid self-lubricating bearing material. The wear mechanism of the tin bronze bearing material is mainly adhesive wear, and that of the aluminum bronze bearing material is mainly grinding wear, oxidation wear and adhesive wear. The copper-embedded self-lubricating bearing materials had no obvious abrasion, whereas the aluminum bronze inlaid self-lubricating bearing material exhibited deep furrows and obvious abrasion under high loads.

These results are helpful for the application of copper-embedded self-lubricating bearing materials.

The paper's aim is to examine dry friction properties of the wear behaviors of the manufactured aluminum bronzes (C9500 and C95300) by using pin‐on‐disk type wear test device.

In this study, alloys were produced by casting C95200 and C95300 aluminum bronzes norms. Produced aluminum bronzes ingot after homogeneous were formed for wearing specimen. These test were conducted on two different alloys, in the sliding velocities 1, 1.5 and 2 m/s, with four different load (25, 37.5, 50 and 62.5 N) and for four different space (500, 1,000, 2,000 and 4,000 m). Wearing specimens tested for hardness and investigated in order to spectral electron microscope photographs.

After investigation, C95200 grain size was bigger than C95300. Furthermore, C95300 alloys were harder than C95200 because of more aluminum. Increasing load, sliding velocity and distance causes increasing wear. Coefficient of C95200 alloys was higher than C95300.

Aluminum bronzes show different properties according to the additional elements in them. Reliability of aluminum bronzes can be achieved by the control of chemical composition and the manufacturing method.

Very useful information for industries using or planning to produce C95200 and C5300 alloys is provided.

This paper identifies a resource need and offers practical help for a manufacturing operation.

Nickel-aluminum bronze (NAB) has been widely used in ship propellers. It is always subjected to local micro-plastic deformation in service environments. This paper aims to study the influence of plastic deformation on the mechanical strength and corrosion resistance of NAB in 3.5 Wt.% NaCl solution.

Scanning electron microscope and X-ray diffraction were used to analyze the microstructure of NAB alloy with different plastic deformations. Mechanical properties of the sample were measured by tensile experiment, and corrosion behavior was studied by electrochemical measurements and the long-term immersion corrosion test.

Results showed that the plastic deformation caused lattice distortion but did not change the microstructure of NAB alloy. Microhardness and yield strength of NAB were significantly improved with the increase of deformation. The lattice distortion accelerated the formation of corrosion product film, which made the deformed alloy show a more positive open-circuit potential and an increased Rp. However, during the long-term immersion corrosion, the corrosion resistance of NAB alloys deteriorated with the increase of plastic deformation. This is because larger plastic deformation brought about higher internal stress in corrosion product film, which resulted in the premature peeling of the film and the loss of its protective effect on the alloy substrate.

Tensile plastic deformations were found to cause a decline in the corrosion resistance of NAB. And the mechanism was clarified from the evolution of corrosion products during the corrosion process.

The purpose of this study is to investigate the influence of the printing temperature on several tribological parameters.

Polylactic acid (PLA) samples are produced at different printing temperatures. Results for the influence of the printing temperature on linear wear, wear intensity, wear resistance, roughness and microhardness in condition of reverse sliding friction of tribosystems with two different types of counterbodies were obtained.

In view of the experiments performed and a thorough analysis of the data obtained, it can be concluded that the printing temperature of PLA parts is directly related to their wear resistance – the higher the printing temperature, the greater the wear resistance, i.e. when making PLA machinery elements (which are working under conditions of friction and wear, e.g. gears, plain bearings and so on), it is appropriate to print them at a higher temperature.

To the best of the authors’ knowledge, the topic of this study is original and essential for future developments.

This paper aims to confirm that increasing the hardness of thrust collars can improve the load carrying capacity (LCC) and wear resistance of water lubricated thrust bearings (WTBs) made of polymers paired with non-polymeric thrust collars, and to design a WTB with high LCC and durability for a shaftless pump-jet propulsor of an autonomous underwater vehicle. Six kinds of WTBs were manufactured by matching aluminum bronze, stainless steel and silicon nitride with two different polymer bearing materials. Their tribological behaviors were tested and compared.

The tribological behaviors of the WTBs made with different materials were investigated experimentally on a specially designed test rig.

Aluminum bronze is not suitable for crafting thrust collars of heavy load WTBs due to severe abrasive wear. Two body abrasive wear first occurred between the thrust collar and the polymer bearing. Next, aluminum bronze wear particles were produced. The particles acted between the two materials and formed three body abrasive wear. Stainless steel/polymer bearings showed better wear resistance while Si₃N₄/polymer bearings were the best. Improving the hardness of thrust collars is significant to the LCC and service life of WTBs.

The wear mechanism of WTBs under heavy load conditions was revealed. Improving the hardness of the thrust collar was confirmed to be a preferable method to improve the wear resistance and LCC of WTBs. The results of this study may provide an important reference for the selection of water lubricated materials and the design of heavy load WTBs.

The purpose of this study was to investigate the polyacrylic polymer/Al₂O₃ as a new nanocomposite coating to protect brass and Al-bronze in 3.5% NaCl and the role of alumina formulation on their protection efficiency

The corrosion efficiency of the nanocomposite coating (NCC) was evaluated by open circuit potential and electrochemical impedance spectroscopy (EIS).

The protection efficiency was more in the case of Al-bronze even for the same formulation of alumina NCC indicated the Cu substrate contribution. The Cu oxides in alloys and Al₂O₃ from the NCC and Al-bronze were responsible for this protection.

All the techniques supported each other, the presence of alumina was responsible for the corrosion protection efficiency.

This study aims to study the tribological performance of sunflower TMP ester and silica nanoparticles additives as a biolubricant alternative to the conventional lubricants for hydrodynamic journal bearing applications.

Nanolubricants were synthesized using an ultrasonicator and a homogenizer. A pin-on-disk tribometer was used to simulate the boundary lubrication condition for hydrodynamic journal bearing application in the presence of the studied lubricants. Surface analysis of the pin (bearing material) was done using scanning electron microscopy and energy dispersive X-ray spectroscopy.

The sunflower TMP ester performed well in terms of the coefficient of friction compared to commercial lubricants, but its wear performance was poor. The silica nanoparticles improved the wear and friction performance of the sunflower TMP ester. With the addition of 1% silica nanoparticles to sunflower TMP ester, the reduction in the coefficient of friction was 27.92% and the reduction in specific wear rate was 54.79%, making it the best lubricant out of all studied lubricants.

Although there are various available studies on vegetable oil-based lubricants for hydrodynamic journal bearing applications, the studies on the use of vegetable oil-based TMP esters for hydrodynamic journal bearing applications are limited. Also, the effect of silica nanoparticles on the tribological performance of TMP esters under boundary lubrication condition has not been studied extensively in the available literature.

The purpose of this research paper was to investigate the use of methanolic extract of Salvia hispanica (S. hispanica) as a green corrosion inhibitor for bronze in a simulated acid rain solution.

Extract of S. hispanica was used as a green corrosion inhibitor for bronze in simulated acid rain solution. Electrochemical techniques such as potentiodynamic polarization curves, electrochemical impedance spectroscopy and electrochemical noise were used. Parameters such as polarization, charge transfer and noise resistance (Rp, Rct and Rn, respectively) were calculated.

Results showed that the extract acts as a good, anodic type of inhibitor. The inhibitor efficiency increased with increasing its concentration up to 400 ppm, decreasing beyond this concentration. Efficiency also increased with an increase in the immersion time. The inhibition was due to the adsorption of components found in the S. hispanica extract following a Langmuir adsorption isotherm.

S. hispanica extract can be used as a corrosion inhibitor for bronze in acid rain solution.

This study provides new information on the inhibition features of S. hispanica under specific conditions. This eco-friendly inhibitor could find applications to protect bronze exposed to polluted urban atmospheres.

The purpose of this paper is to study the frictional behaviors of CuAl10Fe3 journal bearings sliding against chromium electroplated 42CrMo shafts and diamond-like carbon-coated 42CrMo shafts, respectively, under two different conditions and to compare the two kinds of friction pairs.

All journal bearing samples underwent 24 h running-in and repeatability verification. Then, the journal bearing friction experiments were carried out under two different conditions. After testing, the torques, friction coefficients, power consumptions and other parameters were obtained.

The pair of CuAl10Fe3 journal bearing and diamond-like carbon–coated shaft could drive greater load to start up than the pair of CuAl10Fe3 journal bearing and chromium electroplated 42CrMo shaft, but it had greater power consumption during the steady running period under the identical condition. With the changing of specific pressure or rotational speed, the friction coefficients had different variations. The frictional oscillations appeared at 32 rotations per minute under heavy loads for both kinds of pairs, the oscillation frequencies were equal to rotational frequency of the test shaft and the oscillation amplitude for diamond-like carbon coating was much greater.

These results have guiding significance for practical industrial applications.

The purpose of this paper is to outline some key aspects such as material systems used, phenomenological and statistical process modeling, techniques applied to monitor the process and optimization approaches reported. All these need to be taken into account for the ongoing development of the SLM technique, particularly in health care applications. The outcomes from this review allow not only to summarize the main features of the process but also to collect a considerable amount of investigation effort so far achieved by the researcher community.

This paper reviews four significant areas of the selective laser melting (SLM) process of metallic systems within the scope of medical devices as follows: established and novel materials used, process modeling, process tracking and quality evaluation, and finally, the attempts for optimizing some process features such as surface roughness, porosity and mechanical properties. All the consulted literature has been highly detailed and discussed to understand the current and existing research gaps.

With this review, there is a prevailing need for further investigation on copper alloys, particularly when conformal cooling, antibacterial and antiviral properties are sought after. Moreover, artificial intelligence techniques for modeling and optimizing the SLM process parameters are still at a poor application level in this field. Furthermore, plenty of research work needs to be done to improve the existent online monitoring techniques.

This review is limited only to the materials, models, monitoring methods, and optimization approaches reported on the SLM process for metallic systems, particularly those found in the health care arena.

SLM is a widely used metal additive manufacturing process due to the possibility of elaborating complex and customized tridimensional parts or components. It is corroborated that SLM produces minimal amounts of waste and enables optimal designs that allow considerable environmental advantages and promotes sustainability.

The key perspectives about the applications of novel materials in the field of medicine are proposed.

The investigations about SLM contain an increasing amount of knowledge, motivated by the growing interest of the scientific community in this relatively young manufacturing process. This study can be seen as a compilation of relevant researches and findings in the field of the metal printing process.