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Highlights Determining the appropriate formulation in designing and developing brake friction materials is one of the most complex tasks. This study investigates the synergistic effect and optimization of twaron fiber on the fade and recovery performance of brake friction composites. For this purpose, a series of friction materials containing varying amounts of twaron between 1 and 9 wt% were developed, and their characterization and tribo evaluation were carried out. The tribo performance of the composites was evaluated in a Krauss‐type friction test machine in line with the ECE R90 procedure in terms of their fade and recovery behaviors. It was noted that the fade‐recovery friction response of composites was affected when fiber is added; that is, an increase in fiber content improved the fade performance, friction fluctuations decreased, and a higher recovery response was observed. The fade and average coefficient of friction were found to be the main determinants, while recovery was found to be the stabilizer. Analytical hierarchy process (AHP) was used to determine the priority of importance of criteria in the performance evaluation, and VIKOR (multi‐criteria optimization compromise solution) was used for ranking evaluation. The formulation with a concentration of twaron 7 wt% was found to have exhibited an optimal braking performance. The worn surfaces scanning electron microscope (SEM) study confirms the general friction and wear mechanisms of friction layers with fiber content. Development of twaron pulp‐reinforced eco‐friendly brake friction composites. Use of MCDM approach in the development of BFCs for braking applications. VIKOR optimization positioned 7 wt% twaron‐addition BFC as the optimal choice. It was observed that fiber amount is effective on the behaviors of composites. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Materials and Methods Results Conclusion Clinical Significance To evaluate the effect of staining, glazing, and polishing of stabilized zirconia with 5 mol% of yttrium oxide (5Y‐TZP) on the wear behavior of opposing tooth enamel.The plane specimens of 5Y‐TZP were divided into 6 groups (n = 10), according to surface treatment: as sintered, staining, glazing, polishing, staining followed by glazing, and staining followed by polishing, and positioned against tooth enamel during the two‐body wear test (20 N, 2 Hz, until completing 300,000 cycles). The wear rates of tooth enamel were evaluated using a profile projector and a digital pachymeter as a measure of vertical height loss. The data were analyzed by one‐way ANOVA and a Tukey post hoc test (α = 0.05).Polishing reduced the vertical height loss (p < 0.001) while there was no difference among other groups.Polishing is recommended as a finishing procedure to reduce the wear rates of tooth enamel, and finishing procedures (glazing or polishing) performed after staining did not affect the vertical height loss of tooth enamel.Polishing is the recommended finishing procedure for preshaded 5Y‐TZP to reduce the wear rates of opposing tooth enamel. Staining is applied to the occlusal surface to reproduce the pigmented groove appearance, and glazing or polishing performed after staining did not affect the wear rates of opposing tooth enamel. [ABSTRACT FROM AUTHOR]

The widespread availability of banana peels makes them an excellent resource for bio-fillers in developing environmentally conscious and biodegradable composites, serving as substitutes for plastic and synthetic waste. This study focuses on using banana peel waste as a bio-filler to produce lighter and cheaper materials. The extracted banana peels were subjected to alkali treatment to improve interfacial interaction, and their crystalline performance, functional categories, and morphological studies were examined using XRD, FTIR, and SEM techniques. Composite samples were fabricated with varying bio-filler ratios (0.0, 2.5, 5.0, 7.5, and 10%) to examine their thermo-mechanical and tribological attributes. The inclusion of banana peel in the epoxy matrix at up to 5% significantly enhanced mechanical performance, while 7.5% composites demonstrated higher thermal endurance with a degradation temperature of 395 °C and reduced water retention. Frictional wear of the specimens was assessed by varying sliding speeds under different loads, with the highest coefficient of friction and temperature observed under a 30 N force for BPC-10.0 specimens. This research innovatively uses banana peel powder (approx. 65 µm) to create polymeric composites, addressing the need for sustainable materials with higher specific modulus and strength compared to conventional substances. The study uniquely evaluates the physical, mechanical, structural, and tribological efficiency of raw and processed banana peel particles, with chemical modifications improving crystallinity and interfacial bonding. This comprehensive approach provides vital insights for developing sustainable alternatives to reduce plastic usage. [ABSTRACT FROM AUTHOR]

This study focuses on the creation of high degree biocomposite with the utilization of renewable resources, including cardanol oil, palm kernel fiber and chitosan biopolymer. The principal aim of this research was to achieve high degree ratio of biocomposite for safe and eco-friendly application. The chitosan biopolymer was extracted from marine waste sea urchin spikes via deproteination. The biocomposites were prepared via hand layup technique following testing via ASTM standards. According to results, among the composites fabricated, PC5 exhibits exceptional mechanical strength with tensile strength of 88.2 MPa, flexural strength of 133.35 MPa and impact energy of 3.92 J. Therefore, PC6 composite performs better wear resistance with reduced coefficient of friction of 0.399 and Sp. wear rate of 0.01 mm3/Nm, respectively. And also, PC6 provides good thermal resistance with initial decomposition temperature of 345 °C. Similar to mechanical properties, in fatigue behavior also PC5 exhibits high fatigue life cycle counts with 19,647 for 25% UTS, 18,799 for 50% UTS and 17,571 for 75% UTS. The obtained results show that the inclusion of palm kernel fiber and chitosan significantly enhances the mechanical properties, wear and thermal resistance of the composites, while the cardinal oil binder ensures proper adhesion. However, thermal aging conditions were implemented to assess the material's ability to withstand harsh environmental factors. Notably, among the composite materials tested, the designations with chitin (such as PC4, PC5, and PC6) exhibited lesser susceptibility to the effects of thermal aging. This resilience is attributed to the presence of NH2 functional groups within chitin, which play a role in reducing the impact of thermal aging. These discoveries highlight the promising qualities of the developed polyester biocomposites, suggesting their suitability for a wide array of industrial applications requiring materials capable of enduring high-temperature environments such as automotive door panels, structural, space, defense and sports applications. [ABSTRACT FROM AUTHOR]

ABSTRACT The study investigated the potential of waste plastic oil (PO) as an alternative to petroleum‐based lubricants, specifically mineral oil. The rheological properties, dispersion stability, friction, and wear performance of PO were examined and compared with mineral oil. Results showed that PO demonstrated similar lubrication performance to mineral oil. To enhance the lubrication performance of PO, the study incorporated various concentrations of nano CuO solid lubricant additives, resulting in the formation of CuO nano lubricants. These lubricants showed an improvement in friction and wear by 20% and 44% compared with PO. Furthermore, the CuO solid lubricant additives were functionalized and incorporated in the same concentrations into PO, resulting in the formation of functionalized nano lubricants, which further lowered the friction and wear by 28% and 91% compared with PO. The novelty of the paper is that a simple chemical functionalization process that not only helped in improving its dispersion stability of additives in the PO, but also enhanced the wear performance. The mechanisms behind the enhancement of friction and wear performance were discussed. Based on these findings, it can be concluded that incorporating functionalized nano additives in PO improve friction and wear performance in mechanical components, promoting wider utilisation of PO. [ABSTRACT FROM AUTHOR]

Acetabular cup liners made of ultra‐high molecular weight polyethylene (UHMWPE), in hip implants fail mostly due to wear debris generation and poor wear resistance. Consequently, strengthening UHMWPE becomes essential. The current work exhibits how the addition of 5 vol% carbon nanotubes (CNT) and functionalized carbon nanotubes (fCNT) in UHMWPE (denoted as U) affects the mechanical properties (hardness, elastic modulus) and tribological properties (wear resistance) of biocomposites. To form a composite, powders were mixed using a planetary centrifugal mixer followed by freeze‐drying to disperse‐CNTs, followed by its compression molding at 220°C for 1 h at 10 MPa. With the addition of CNT and fCNT, ≥95% densification was obtained for all samples resulting an increase in hardness and elastic modulus from 74.96 MPa to 168.11 MPa (124%) and 1.65 GPa to 2.96 GPa (79%), respectively, which led to the reduction in wear rate from 12.5 × 10−5 mm3/Nm (U) to 2.5 × 10−5 mm3/Nm (UfCNT). The amount of apatite formation enhanced from U (58.2%) to UfCNT (65.1%) is confirmed via X‐ray diffraction and X‐ray photoelectron spectroscopy. Cell proliferation studies have validated the cytocompatible efficacy of U‐CNT composites with osteoblast‐like MG‐63 cells, making UfCNT as potential material for acetabular cup liners. [ABSTRACT FROM AUTHOR]

To improve the tribological performance of SS410 steel in seawater, TiCrN and CrSiN coatings were deposited using PVD sputtering and thoroughly analyzed. The CrSiN coating, which exhibits higher hardness and better corrosion resistance, achieved a protective efficiency of 83.70%, surpassing the TiCrN coating by 14% according to anodic polarization tests. Friction and wear properties were evaluated with a ball-on-disk tribometer in artificial seawater, following ASTM G77 standards. The CrSiN coating demonstrated lower friction coefficients and wear rates—1.362 × 10⁻⁶ mm3/N-m compared to 2.632 × 10⁻⁶ mm3/N-m for TiCrN at a 4N load—highlighting the positive impact of Si addition. These coatings markedly enhance the tribocorrosion resistance of AISI 410 steel, addressing issues in marine engine components, extending their service life, and ensuring reliable performance in severe marine conditions. SEM analysis of the uncoated SS410 surface revealed pits and deep grooves. [ABSTRACT FROM AUTHOR]

Polymer coatings have gained a lot of attention in the recent past because of their ability to be easily coated on complex shapes, their low cost, and their ability to reduce friction as compared to other materials. Polyether ether ketone (PEEK) is one such high-performance polymer that has gained significant attention in recent years due to its exceptional mechanical properties, chemical resistance, and thermal stability making it a prominent candidate for applications in industries. However, PEEK in its pristine form exhibits poor wear resistance with a moderate coefficient of friction (0.30–0.38). Many attempts have been made by several researchers to improve its wear resistance and lower the COF by developing composite coatings. Hence, in this review, we aim to summarize and present in detail the tribological evaluation of pristine PEEK and PEEK composite coatings by discussing the various methods adopted by the researchers to improve the properties of PEEK, the different types of reinforcements and various dispersion techniques used to develop PEEK composite coatings. By consolidating and analyzing the existing body of knowledge, we also aim to offer valuable insights into the development of more durable, high-performance PEEK nanocomposite coatings for a broad range of tribological applications. [ABSTRACT FROM AUTHOR]

This study examined the development of Fe2B (diiron boronize) coatings on the surface of 35NiCrMo4 steel through the thermochemical surface hardening process called boronizing. The morphology and thickness of the boronize coatings were assessed using Scanning Electron Microscopy (SEM) and optical microscopy (OM). A novel mathematical mass transfer model was developed to estimate the diffusion coefficients of boron in hard coating. The presence of uniformly distributed boronize coatings with a typical sawtooth pattern on the surface of the substrate was confirmed. The boronize coating's chemical composition and phase constituents were analyzed utilizing X-ray energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (XRD). The study confirmed the presence of a single-phase boronize coating (Fe2B). Furthermore, microhardness tests indicated that the boronized specimen's surface demonstrated an average hardness of approximately 1953 HV. The wear study were conducted using the pin-on-disk method under dry debonding conditions at room temperature to estimate the coefficient of friction (COF) of the boronized (average ≈ 0.35) and untreated (0.725) specimens. The results revealed approximately 200% improvement in wear resistance due to the boronized coating. The empirical validation of the mathematical model was carried out for two additional boronizing conditions at 1223 K for 3 h and 1273 K for 1.5 h, resulting in an estimated percentage error of around 2.5% for both conditions. Additionally, an ANOVA analysis was performed, taking into account the temperature and time factors. The findings indicate that both factors exert a substantial influence on the dependent variable (u), with temperature (T) contributing 64.68%, time (t) contributing 27.37%, and the interaction of both factors (T × t) contributing 5.13%. [ABSTRACT FROM AUTHOR]

A problem has been noted regarding the admixture of fuel to a low viscosity lubricant in hybrid electric vehicles (HEVs). This is very detrimental to the wear and tear of engine operating components. In this study, the operating conditions of HEVs were analysed. Using X-ray fluorescence spectrometry (XRF), engine oils of two different viscosity classes were compared after the operating process and these data were compared with fresh reference samples. Attention was paid to the content of elements such as Ca, Zn, Mo, Sn, Cd, Fe Pb, Si, Cu, and Ni. The depletion of anti-wear additives, as well as the higher content of metallic wear products relative to the operated 5W30 (engine oil), contributed to the overall assessment of the lubricity of the 0W30 oil, as well as to the tribological results. Then, under laboratory conditions, oil samples contaminated with up to 1 to 8% fuel were subjected to rheological (mini AV-X viscometer) and tribological (four-ball tester) tests. The dependence of the local pressure at the metal-to-metal contact point in the kinematic node on viscosity showed the dissimilar nature of the used and fresh oil and the divergence of the domains for the two groups of samples. Increasing the fuel contamination of used oil above 4% drastically reduces the pressure responsible for maintaining the oil film. In order to improve lubricant performance during HEV operation in urban conditions, it was proposed to carry out extra-urban traffic driving in order to evaporate the fuel from the engine oil. A shorter oil change interval is also recommended. [ABSTRACT FROM AUTHOR]

Objectives: This study evaluated the mechanical, optical, microstructural, surface, and adhesive behavior of a 3D printing resin comparing it with a machinable resin composite. Materials and methods: Specimens of different sizes and shapes were either printed (Vitality, Smart Dent) or machinable (Grandio Blocs, Voco GmbH) resin composites with similar composition were prepared. Surface and mechanical characterization were performed with Knoop hardness, flexural strength (three-point-bending), and elastic modulus tests. The wear of the tested materials was evaluated against steatite antagonists. The optical properties stability (color change, ΔE00, and translucency, TP00) were observed after staining in red wine. In addition, the bond strength of the resin composites to two resin cement protocols were investigated with microshear bond strength tests at baseline and after thermocycling. Scanning electron microscope (SEM) coupled with Energy-Dispersive X-ray Spectroscopy (EDS) was used for microstructural and chemical characterization. Statistical analyses were performed with t- and ANOVA tests. Results: Hardness values (132.76 (16.32) KH- Machinable and 35.87 (2.78) KH - Printed), flexural strength (172.17 (26.99) MPa - Machinable and 88.69 (8.39) MPa - Printed), color and translucency change (1.86 (0.31)/0.06 - Machinable and 3.73 (0.36)/9,16- Printed), and wear depth (24.97 mm (3.60)- Machinable and 7.16 mm (2.84) - Printed) were statistically different. Average Regarding bond strength, mean values (MPa) for non-aged and aged groups were respectively 21.76 (6.64) / 31.9 (12.66) for Bifix cement (Voco GmbH, Cuxhaven, Germany) and 26.75 (5.14) / 24.36 (6.85) for Variolink cement (Ivoclar Vivadent, Schaan, Liechtenstein) in Printed and 17.79 (3.89) / 9.01 (3.36)) for Bifix cement and 22.09 (6.55) / 11.01 (3.77) for Variolink cement in Machinable materials. The material and aging factors did affect bond strength but the cement factor did not (p = 0.202). No statistical differences were observed for mean roughness (Ra) between materials. The better dispersion and larger size of the inorganic particles in the Machinable resin were contrasted with the clustered smaller particles of printed resin, under SEM. Conclusions: The mechanical properties and color stability of the machinable resin were superior to those of the printed resin, probably due to the greater amount and dispersion of inorganic particles in the Mach resin, but bond strength after aging was stronger and more stable in the printed resin. Clinical relevance: 3D-printed resin composites with similar compositions to machinable resin composites do not necessarily exhibit the same properties, which can impact clinical performance. Understanding these differences can assist manufacturers in improving their materials and help clinicians distinguish between materials appropriate for provisional and final restorations. [ABSTRACT FROM AUTHOR]

Refractory High entropy alloy (RHEA) is a potential material for coating gas turbine blades and pipeline due to its high-temperature mechanical and chemical properties. In this paper, a series of new NbTiCrFeMoX (x = 0.2, 0.4, 0.6, 0.8, 1) RHEAs were coated on GTD-111 nickel base superalloy by the laser cladding method. The effects of the Mo amount on the microstructure and tensile, creep, corrosion, and wear properties were investigated. XRD results showed that the microstructure of all five coatings included the B2 regular phase, the BCC irregular phase, C14-Laves (FeTi2), and C15-Laves (Cr2Nb). However, with the increase of Mo from 0.2 to 1, the amount of the BCC phase increased from 24.1 to 29.5%, the C14 phase increased from 55.1 to 61.4%, and the amount of the C15 phase decreased from 11.2 to 1.8%. The yield strength increased by increasing the volume fraction of BCC and C14-Laves phases from 328 MPa for the Mo0.2 sample to 685 MPa for the Mo1 specimen. The same factor increased the creep life of RHEA from 43 to 54 h under a force of 450 N and temperature of 800 °C by increasing the places of dislocation locking. The simultaneous presence of the BCC solid solution and Laves phase was one of the factors that reduced the coefficient of friction during the wear test from 0.63 to 0.44 with increasing Mo. Electrochemical tests in 3.5 wt% NaCl solution showed that the RHEAs showed significant corrosion resistance. Specimen Mo1 with the smallest Icorr (1.6103 × 10–6 A cm2) and the highest Ecorr (− 1.2025 V) showed the best corrosion resistance. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic behavior of one degree-of-freedom oscillator subject to stick–slip and wear phenomena at the contact interface with a rigid substrate is investigated. The motion of the oscillator, induced by a harmonic excitation, depends on the tangential contact forces, exchanged with the rigid soil, which are modeled through piecewise nonlinear constitutive laws, accounting for stick–slip phenomena due to friction as well as wear due to abrasion, already developed by the authors in a previous work. The nonlinear ordinary differential equations governing the problem are derived, whose solution is numerically obtained via a typical Runge–Kutta-based algorithm. The main target of this study is to analyze and discuss the strong nonlinear behavior, descending from the presence of stick–slip and wear phenomena, thus investigating the effect of the different interface modeling. In this framework, the analysis is carried out considering the whole evolution of non-smooth contact laws, starting from the virgin interface. [ABSTRACT FROM AUTHOR]

In this study, Bi alloy AA1100/TiO2/AA5083 composites were produced by accumulative press bonding (APB) for the first time. In the first step, two bars of aluminum alloys 1100 and 5083 with 5 wt.% of uniformly scattered TiO2 particles were stacked together and pressed with a 50% reduction ratio. Then, this process was continued up to six steps. Corrosion properties of composites were studied by potential dynamic polarization and electrochemical impedance spectroscopy measurement in 3.5 wt.% NaCl solution. So, in this investigation and as its novelty, a considerable improvement was revealed in the main electrochemical parameters as a result of enhancing the influence of APB steps and the inert character of the particles. Moreover, using the wear test, the wear resistance of these bi alloy composites has been studied vs the APB steps. Also, the wear and electrochemical experiments showed that corrosion and wear resistance of samples were improved by the APB steps by 70% and 34%, respectively. [ABSTRACT FROM AUTHOR]

Large gas engines are typically applied to compensate for peak loads and grid instabilities in the electric power supply. A key component of these engines is the spark plug. Because of the harsh conditions encountered in their use, the spark plug electrodes are subject to significant wear. Conventional electrodes are expensive due to the precious metal alloys they contain. As an alternative, ceramic materials from the groups of silicide, carbides, and nitrides were selected for preliminary experiments that investigate functional as well as mechanical properties and wear behavior. Because of the harsh conditions during operation, the new materials must have a high melting temperature, good thermal shock resistance, high thermal conductivity, and high corrosion/oxidation resistance as well as high density. It was found that the mechanical and thermomechanical properties of certain ceramic candidates are sufficient for application as spark plug electrodes. Furthermore, the chosen ceramic materials achieve an adequate performance in terms of secondary voltage trace and ignition behavior. However, wear resistance may not be sufficient for service times longer than the service time of existing spark plugs and further research is still necessary before ceramic electrodes may be established as a commercial alternative to existing electrodes. [ABSTRACT FROM AUTHOR]

Wire arc additive manufacturing (WAAM) causes significant heat accumulation within the deposited layers making it difficult to achieve necessary geometrical accuracy and built properties. A cost-effective technique to mitigate build-up heat and improve the thermal cycle is accomplished with the introduction of an inter-layer dwell time (ILDT). The study investigates the impact of ILDTs of 60, 90, 120, 150, and 180 s on the properties of the printed parts. The grain refinements were achieved at higher ILDT with no appreciable changes in the compositions. However, a slight increase in oxides and δ -ferrite was detected. The study found improved part density, mechanical and tribological performance while reduced corrosion-resistant properties with increased ILDT. Furthermore, to understand the effect of ILDTs on location-based thermal cycling and distribution, numerical models of the process were established. The peak temperature gradually reduces with an increase in ILDT. Heat accumulations within the three-layered WAAM-built structure lessen by 70% approximately with increases in ILDT from the 60 s to 180 s. The results observed repeated thermal cycles of the previously deposited layers and reduction of peak temperatures with subsequent layer deposition irrespective of the ILDTs. The trough temperature slightly reduced with ILDT; however, at higher delay periods the variations were found to be more stable. The study discovered too low and too high ILDT is detrimental and therefore an appropriate mid-range ILDT of 120 s is suggested to fabricate medium-size WAAM-built components based on experimental and numerical investigation considering overall production time and functional properties. [ABSTRACT FROM AUTHOR]

This research involves the synthesis of a hybrid composite by adding titanium carbide (TiC) and hexagonal boron nitride (hBN) powders in certain weight ratios (2.5–5%) to pure aluminum (Al) powder. When previous studies were examined, it was seen that TiC and hBN powders were added separately to Al matrix powders; however, a hybrid composite was not produced as in this study. The obtained hybrid composites were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and X-ray diffraction (XRD) analysis. Microstructure, hardness and wear tests were carried out under 3 different loads (10 N, 20 N and 30 N) and dry conditions. Weight loss and coefficient of friction measurements were obtained for each hybrid composite during the wear tests. The TiC–hBN-reinforced specimen exhibited a significantly higher hardness value of 37.08% compared to the pure Al composite. It was also found that the synthesized Al–TiC–hBN hybrid composite exhibited a 59% reduction in the wear loss value for 10 N load, 30% for 20 N load and 60% for 30 N load compared to the pure Al sample. It is believed that the hybrid composites produced in this study have the ability to compete with Al matrix materials and exhibit the potential for longer durability and cost reduction in industries that use the production of aluminum parts. [ABSTRACT FROM AUTHOR]

In the study, the effects of hybrid reinforcement (nano-alumina and MWCNT) and heat treatment on the wear behavior of the Al–4Cu nanocomposites were investigated under dry sliding condition against W–6Co ball by means of a ball-on-disk type tribometer. The load and the sliding speed were kept constant and selected to be 10 N and 0.1 m s−1, respectively, in the course of the wear tests. Meanwhile, the wear tests were completed after a total sliding distance of 1500 m was reached for each case. During these tests, the wear loss of the nanocomposites was measured at every 250 m. The worn surfaces of the nanocomposites were examined with the help of stereo and scanning electron microscopes. The volumetric wear rates, wear coefficients and wear mechanisms were identified for the nanocomposites to clarify the influence of reinforcement content and heat treatment on their wear resistance. The volume loss at the wear distance of 1500 m was obtained as 24.9 and 8.2 mm3 for the annealed and aged Al–4Cu alloy, respectively. On the other hand, it decreased to 4.6 and 3.2 mm3 in the case of the nanocomposites with 15% hybrid reinforcement in the annealed and aged conditions, successively. Moreover, increasing the hybrid reinforcement amount decreased the wear loss of the aged nanocomposites substantially in such a way that it resulted in the mild wear. [ABSTRACT FROM AUTHOR]

This investigation is dedicated to producing hybrid nanocomposites based on AA2024, achieved through the utilization of powder metallurgy methods encompassing mechanical milling and hot pressing. The research focused on studying how changes in B4C content influence the mechanical, wear, and corrosion behavior of AA2024/h-BN/B4C hybrid nanocomposites. The findings revealed that as the B4C content increased, the relative density values decreased, and higher porosity values were observed in the hybrid nanocomposite samples. Among the tested samples, the hybrid nanocomposite with 4 wt% B4C exhibited the most favorable properties. It demonstrated significantly higher hardness and ultimate tensile strength compared to AA2024 matrix alloy, with values of 161 HB and 372 MPa, respectively. In contrast, the matrix alloy showed hardness and ultimate tensile strength values of 105 HB and 237 MPa, respectively. Furthermore, the wear resistance of hybrid nanocomposite with 4 wt% B4C displayed approximately 14 times greater wear resistance under 40 N load compared to the unreinforced AA2024 matrix alloy. The corrosion test results have revealed that the corrosion resistance of the hybrid nanocomposite reinforced with 4wt% B4C is nearly 47% higher compared to the corrosion resistance of the unreinforced AA2024 alloy. This nanocomposite exhibits the highest polarization resistance of 5.21 Ω.cm2. [ABSTRACT FROM AUTHOR]

This study examines the impact of Friction Stir Processing (FSP) with TiO2 nanoparticle incorporation on the microstructural, mechanical, and tribological properties of AA5083 Metal Matrix Composites (MMCs). It offers a detailed analysis of the alterations in the alloy’s characteristics due to FSP. Microstructural examination was conducted using optical microscopy (OM) and scanning electron microscopy (SEM). Significant findings include the microstructural refinement where TiO2 nanoparticle addition during FSP shrank the grain size from 20 to 3 µm after one pass, which then rose to 7 µm following four passes. Mechanical properties, specifically microhardness and tensile strength, were assessed. Results indicated that after four FSP passes, the material can reach a yield strength of 192 MPa and an ultimate tensile strength (UTS) of 359 MPa, alongside a consistent microhardness of 103 HV0.1. Furthermore, it was observed that increasing FSP passes enhances energy absorption, although it remains lower than that of the base material. Analysis of fracture and wear mechanisms has led to the conclusion that with more passes, fracture mechanisms transition to a mix of ductile and brittle behaviors, and the friction coefficient decreases by up to 22.95%. [ABSTRACT FROM AUTHOR]

Solid lubricants are added to polymers to upgrade their tribological properties, especially in cases where adhesive and abrasive friction are valid. However, there are not enough studies on the effects of solid lubricants on particle erosion. This study investigated the effects on solid particle erosion behavior of three different well known solid lubricants (molybdenum disulfide, polytetrafluoroethylene, and graphite). These solid lubricants were added at three different ratios (5, 10, and 15 wt.%) to the two different type (rigid and toughened) epoxy resins. Garnet abrasive particles (180–400 μm) were blasted to the sample surface under 1.5 bar for 15 s to conduct solid particle erosion tests. The erosive wear mechanisms of neat and solid lubricant‐reinforced epoxy resins were investigated in relation to the epoxy type, solid lubricant type, and solid lubricant reinforcement ratio. Statistical analysis was performed according to response surface methodology to support the experimental results, and ANOVA tables were obtained. The wear and deformations that occurred on the surface after solid particle erosion were examined using a noncontact optical profilometer system and scanning electron microscopy, and a significant relationship was detected between the deformation on the surface and particle erosion. Analysis results showed that the factor causing the greatest erosion rate change was the epoxy resin type. Finally, it has been observed that all solid lubricants reduce the erosive wear resistance, and this resistance decreases as the weight ratio increases. Highlights: Investigations were conducted into the erosion behavior of two types of epoxy resins: rigid and toughened. The toughened epoxy resin exhibited greater resistance to erosion. Although it has the same type of content, on average, rigid epoxy worn 2–4 times more than toughened epoxy.The effect of adding polytetrafluoroethylene tended to increase the erosion rate of both rigid and toughened epoxy resin less than that of other solid lubricants.Graphite particles increased the erosion rate of toughened epoxy by 1.5–3 times and that of rigid epoxy by 2–3 times, depending on the value of the reinforcement ratio.MoS2 increased the erosion rate of toughened epoxy by 1.5–3 times and that of rigid epoxy by 2–3 times.Using a noncontact optical profilometer (for investigating surface topography), it was proven that there is a significant relationship between the erosion rate and roughness characteristics. Wear mechanisms were identified by SEM analysis. [ABSTRACT FROM AUTHOR]

In this research epoxy-based biocomposites were developed using novel green pea pod lignin and hybridized pod sheath fibre-bamboo epoxy composite for human prosthetic applications. The outcomes of this investigation demonstrates that the inclusion of lignin, up to 1.0 vol. % yields a tensile strength of 159 MPa, flexural strength of 202 MPa, interlaminar shear strength of 28.6 Mpa, and Izod impact toughness of 5.93 J. In terms of wear resistance, the composite designation with 2.0 vol. % of lignin exhibited lower wear loss of 0.01 g and 0.38 of coefficient of friction. Both the mechanical and wear results are statistically significant with P < 0.05), confirmed by analysis of variance. Additionally, the highest fatigue life counts were recorded for composite with 1 vol. % of lignin with counts of 34,632 cycles for 30% of the ultimate tensile strength. Furthermore, the addition of lignin up to 2.0 vol. % resulted in the lowest contact angle of 82° and water absorption percentage of 0.16%. Scanning electron microscopy analysis indicated that the incorporation of surface-treated fibres and lignin uniformly dispersed and adhered more. Based on these findings, it is evident that the composite containing 40 vol. % of sheath/bamboo hybridized fibre with 1.0 vol. % of lignin in the epoxy matrix represents the most favourable outcome for prosthetic applications. [ABSTRACT FROM AUTHOR]

In this study, the tribological characteristics of TiN, AlTiN, and AlTiCrN coatings sliding against a SUS420J1 stainless steel pin were investigated in atmospheric and vacuum environments. The coatings were deposited on SUS440C substrates using the arc-physical vapor deposition technique. The friction and wear behavior of the coatings were evaluated based on the systematic analyses of the friction coefficient data as well as the physical and chemical state of the wear track. The results revealed that the friction coefficients of the SUS440C specimen and AlTiCrN coatings increased, whereas those of the TiN and AlTiN coatings decreased when the environment was changed from atmospheric to vacuum. It was confirmed that the formation of an oxide layer and adsorption of oxides on the surface were dominant factors that influenced the tribological behavior in the atmospheric environment. On the other hand, the compatibility, oxidation inhibition, and droplets of the surface mainly affected the frictional characteristics in the vacuum environment. The results of this work are expected to aid in the selection of proper coating materials for tribological systems operating in a vacuum. [ABSTRACT FROM AUTHOR]

Gasoline combustion engine is generally the most important part of a car. With this driving unit the car achieves the best ratio between its fuel utilization and weight. In order to comply with required parameters, such as performance, ecology and economy of combustion engines, their regular service inspections and associated maintenance operations must be followed. For testing the operability of these engines, especially for testing the wear of functional pairs of the combustion chamber, we use various methods. The paper deals with detection of wear of combustion engine functional pairs and with subsequent comparison of obtained values with the values declared by the manufacturer. The measurements were carried out on a Suzuki gasoline engine G13BA with a cubature of 1298 cm3 and a total mileage of 160,000 km. [ABSTRACT FROM AUTHOR]

In the present work, TiO2 scaffolds are prepared by space holder technique via powder metallurgy. NaCl (0–20 vol%) is used as the space holder material to process TiO2 scaffolds with varied porosity between 13.70 and 35.41%. The calcination of the TiO2 powders resulted improvement in the density and mechanical properties of TiO2 scaffolds after sintering (at 1500 °C for 2 h). The XRD of sintered TiO2 revealed presence of only rutile phase, whereas the starting TiO2 powders possess both anatase and rutile crystalline phases. Depending on the processing conditions, the Young's modulus and the compression strength of TiO2 measured in the range of 0.68–17.50 GPa and 18.62–360.40 MPa, respectively. A very low COF of 0.104 is evident for TiO2 disk after sliding against Si3N4 ball. Low wear rate of 1.10 × 10–7 mm3/m N was measured for TiO2, and it falls within the mild wear regime. These properties of TiO2 clearly indicate its potential for both the cortical and cancellous bone applications. However, future study needs to be focused on controlling pore morphology of TiO2 scaffolds. [ABSTRACT FROM AUTHOR]

This research aims to examine the impact of carbon nanotubes (CNTs) agglomeration on the microstructure, mechanical properties, and wear behavior of the FeCoNiMn medium entropy alloy. The CNTs were included into the mixture at weight percentages of 1, 1.5, and 2 using mechanical alloying (MA) and spark plasma sintering (SPS). The base alloy displayed brittle characteristics with a compressive strength of 880 MPa and a hardness of 400 HV. The composite containing 2 wt.% CNTs had the lowest hardness (280 HV) and compressive strength (400 MPa). The wear test demonstrated that the presence of agglomerated CNTs led to an increase in weight loss. The base alloy showed signs of adhesive wear on its worn surface, but the composite samples displayed delamination-like wear characteristics. The findings point to an unanticipated decrease in wear resistance and deterioration of mechanical properties brought on by CNT aggregation. [ABSTRACT FROM AUTHOR]

The structural, tribological, mechanical, corrosion, and other properties of materials produced by laser-based powder bed fusion additive manufacturing methods are significantly affected by production parameters and strategies. Therefore, understanding and controlling the effects of the parameters used in the manufacturing process on the material properties is extremely important for determining optimum production conditions and for saving time and materials. This study aimed to determine the optimal laser parameter values for CoCrFeMnNi high-entropy alloy powders using the selective laser melting (SLM) method. The layer thickness was kept constant during experimentation. 5 different laser powers and 10 varying laser scanning speeds were tested, with hatch spacing from 30 to 90%. After determining the optimal laser parameters for SLM, prismatic samples were fabricated in different build orientations (0°, 45°, and 90°), and subsequently, their structural, mechanical, tribological, and corrosion properties were compared. Melt pool morphology could not be obtained at 20—40 and 60W laser powers and at all laser scanning speeds used at these laser powers. At 100 W laser power, 600 mm/s laser scanning speed, and 70% hatch spacing parameters, an ultimate tensile stress of 550 MPa and elongation of 48% were obtained. Among the samples produced in different build orientations, the sample produced with a 0° build orientation exhibited the highest relative density (99.94%), the highest microhardness (201.2 HV0.1), the lowest friction coefficient (0.7025), and the lowest wear and corrosion rates (0.7875 mpy). Additionally, SLM parameters were evaluated to have a significant impact on the performance of all properties of the samples. [ABSTRACT FROM AUTHOR]

Abstract\nHIGHLIGHTSThis work implements a 3D finite element to analyze wear in borided AISI 316 L stainless steel. The 3D model was validated through sliding wear test under a ball-on-flat configuration, following the ASTM G133 standard procedures. ABAQUS software was used with an Arbitrary Lagrangian-Eulerian (ALE) remeshing technique alongside the UMESHMOTION subroutine to apply an elemental level Archard’s equation. The artificial roughening of the worn surfaces due to discretization in finite element sizes was controlled by relating the maximum increment time on each wear step to the element size and the stroke. The study also described the evolution of the stress field and the behavior of the contact area. The maximum stress was estimated after the first indentation, decreasing as the contact area increased, reaching a minimum at the last wear step. The results revealed a good correlation between the experimental and modeled data, with a maximum error of 8.34% in the contact stress and a maximum error of 22% in the wear depth.Implementation of a 3D finite element analysis to model wear under ball-on-flat configuration in borided AISI 316 stainless steel.The finite element analysis provides a better understanding about the stress distribution in the selected configuration.Correlation between numerical modeling and experimental data of wear in a borided material. [ABSTRACT FROM AUTHOR]

Highlights The characterization of S. persica (Salvadora persica) extract, which involved evaluating its antibacterial activity, demonstrated the extract's strong efficacy. Additionally, incorporating it into PMMA/HA showcased the composite's good antibacterial activity. The objective of this work is to evaluate how the incorporation of S. persica extract affects the wear resistance of the dental composite PMMA/HA, considering the critical importance of wear resistance in dental applications. The wear response of this biocomposite was tested against an Alumina ball using a pin‐on‐disc tribometer. Initially, the hydroxyapatite (HA) micro particles demonstrate a remarkable influence on wear behavior when incorporated at an optimal percentage (10%wt). This optimal inclusion rate not only significantly increases the wear rate but also instigates a shift in the wear mechanism, favoring abrasive wear while minimizing adhesive wear comparing to PMMA. The addition of the extract nanoparticles to the composite PMMA/HA decreases the wear rate except the composite containing 10 wt% of each filler. Additionally, it introduces adhesive wear, in addition to the existing fatigue and abrasion wear. Thus, the composite PMMA/HA could accommodate up to 10 wt% of the S. persica extract as the optimal percentage that provides antibacterial activity to this biocomposite without exhibiting a deterioration in wear performance. The evaluation of the effect of incorporating S. persica extract, which provides antibacterial activity, on the wear resistance of the PMMA/HA dental composite generally demonstrates a reduction in this property. The addition of S. persica extract introduces adhesive wear in addition to the fatigue and abrasion wear already present in the PMMA/HA composite. The composite PMMA/HA can accommodate up to 10 wt% of S. persica extract without compromising its wear performance. [ABSTRACT FROM AUTHOR]

As it is known, Polytetrafluoroethylene (PTFE) is one of the most preferred polymeric materials for tribological applications. This study investigates the performance of PTFE and its composites under different tribological conditions. The effects of short glass fiber (GF), carbon particle (CP) and bronze particle (BP) reinforcement agents and their hybrid filling with molybdenum disulfide (MoS2) on sliding, erosive and abrasive wear were examined. Sliding tests were carried out with a ball‐on‐disc test apparatus, erosive wear tests were carried out with solid particle erosion and abrasive wear tests were carried out with a scratch test. It has been found that reinforcement agents improve sliding and abrasive wear resistance but worsen the erosion resistance. The hardness and contact angle of the samples were associated with their wear performances. Topographic and morphological analyzes of worn surfaces were performed using optical profilometer and scanning electron microscopy (SEM), respectively, and wear mechanisms were discussed. Highlights: Filling materials (glass fiber, carbon particle and bronze particle) increase the adhesion and abrasion resistance of PTFE, while decreasing its erosion resistance.The effect of hybrid addition of MoS2 solid lubricant on wear performances depends on the type of filler.There is a correlation between surface properties (hardness and contact angle) and wear performances.Optical profilometer and scanning electron microscopy were used to examine wear mechanisms. [ABSTRACT FROM AUTHOR]

Introduction: Friction drilling is an innovative method in hole-making for sheet metal applications, thin sheets of conventional structural alloy materials like copper, titanium, steel etc., even though there are other methods, such as thermal distortion for thewelding of nuts, riveting of nuts, and threading. For the last hundred years, researchers have focused on studying the development of this technique to maintain strength, hole roughness, hole geometry, hardness etc. It is interested in finding solutions for wear, tool life, and plastic deformation. Method: Friction drilling is also called a green hole-making process because this process uses the friction between the rotating tool and the workpiece. In this research, instead of regular HSS and Tungsten Carbide tools, the H13 tool steel is used, because the H13 steel tool has unique chemical compositions like chromium and molybdenum, which give high toughness, hot hardness, and wear resistance. Diamond-like-carbon (DLC) coating has been used in this research to enhance tool life and AZ31B magnesium alloy is used as the work material. Initially, in this research, the wear stability of the DLC-coated H13 tool was investigated, and later, the tool surface roughness and hole quality were verified. Results and Discussion: The material loss observed for the DLC-coated H13 steel tool in the pin-on-disk test was 0.05 g. This investigation used two different diameter tools, namely 3 and 7 mm. Research has concluded that the 7mmtool is better for friction drilling by seeing the roughness and hole quality. However, the conditions were that the spindle should rotate at 4,000 rpm and the feed rate of the tool to be at 200 mm/rev. [ABSTRACT FROM AUTHOR]

AbstractThe experimental study assessed the impact of choline chloride cation-based ionic liquid (IL), on the dispersion stability and wear characteristics of copper (II) oxide (CuO) nanoparticles (NPs) in synthetic base oil (PAO 10). CuO NPs, averaging 50 nm in size, underwent surface modification using varying concentrations of the IL (0.25%, 0.5%, 0.75%, and 1% by weight). The formulations were subjected to sliding wear tests to evaluate their wear behavior. Analysis of the worn surfaces utilized scanning electron microscopy, energy-dispersive x-ray spectroscopy, and atomic force microscopy. The results indicated that the combination of 0.75% IL and 1% CuO NPs provided optimal dispersion and exhibited effective surface mending, enhancing wear protection by 21.1% than that of PAO 10. The formulation containing 1% IL and 1% CuO NPs demonstrated the highest load carrying capacity among all tested compositions. In terms of wear behavior, the nanolubricant formulations with 0.75% and 1% IL outperformed the lubricant formulation containing 1 wt% of the commercial antiwear additive Zinc dialkyldithiophosphates (ZDDP). [ABSTRACT FROM AUTHOR]

Highlights This study advances the creation of biocomposite materials and serves to reduce and utilize agricultural waste such as pineapple leaf fibers (PALF). In this study, PALF‐reinforced natural rubber (NR) composites with included multi‐walled carbon nanotubes (MWCNT) were analyzed and characterized at various fiber loadings. The PALF content was ranged from 0, 10, 20 to 30 parts per hundred rubber (phr) while the MWCNT content was maintained at 10 phr. A two‐roll mill mixing process followed by molding was employed to fabricate the NR composites. Based on the curing behavior, tribological properties, and morphological analysis, it was confirmed that the hybrid reinforcement of the MWCNT and PALF improved the curing behavior, wear resistance, and morphology of the composites. The wear and friction properties of the composites namely coefficient of friction (COF), frictional force and specific wear rate (SWR) are significantly influenced by the applied loads. The COF of NR/30PALF and NR/30PALF/MWCNT composites is reduced to 0.80 and 0.72 respectively under 15 N of load. Physical properties namely the cross‐link density and swelling behavior of the composites ranged from 3.70 × 10−4 to 5.71 × 10−4 mol/cm3 and 207.81 to 386.17%, respectively. According to the results obtained, the best cure and wear behavior followed by the morphological analysis are observed in NR/30PALF/MWCNT composite. Among the samples tested, NR/30PALF composite exhibited the best performance in both cross‐link density and swelling behavior. It is anticipated that the findings of this study are expected to provide theoretical data for the design and optimisation of high‐performance automotive and footwear applications. NR/30PALF/MWCNT hybrid composite exhibited the shortest tc90$$ {t}_{c90} $$ The addition of MWCNT improved the wear resistance of the composites The reinforcement of PALF at 30 phr possessed the lowest swelling ratio and the highest cross‐link density of the composites The addition of MWCNT decreased cross‐link density of the composites [ABSTRACT FROM AUTHOR]

This study investigated changes in the crystal lattice, tribological properties and friction mechanism of AISI 316 steel irradiated with swift 160 MeV xenon ions. The irradiation process caused the increased roughness of the steel surface and the swelling of the material. The thickness of the irradiated layer increased by about 13 nm. Following irradiation with the fluences 2.5 × 1014 and 3.2 × 1014 (Xe24+/cm2), martensite formed in the surface layer. Fluctuating changes were also observed with respect to the coefficient of friction and the degree of wear of the AISI 316 steel samples. Irradiation also increased the microhardness of the steel. [ABSTRACT FROM AUTHOR]

3D printing has shown promise in the development of notable sensing and health detection devices. Nonetheless, challenges remain in the concurrent development of highly durable wearable sensors with low‐friction surfaces. This challenge serves as a limiting factor in the operational lifespans of these sensors. In this study, a magnetically assisted 3D printing technique is developed to fabricate composites reinforced with magnetic Fe3O4@SiO2 nanochains (NCs) with dimensions of 60.2 µm in length (L) and 0.2 µm in diameter (D), indicating an L:D ratio exceeding 300. By applying a vertical magnetic field and extrusion flow field to the sensor's surface layer, the NCs can be arranged differently (together with the printed textures), reducing the coefficient of friction by 27.7% and improving the wear resistance. This approach is inspired by nacre, known for its impressive durability and resilience. A motion monitoring sensor with an extended lifespan is successfully fabricated by using liquid metal ink integrated with an anti‐wear layer. These findings offer significant insights into the evolution of wearable sensors, demonstrating their adaptability to multi‐material printing and resulting in improved performance and service lives. [ABSTRACT FROM AUTHOR]

This article presents wheel wear in light rail traffic and the friction behavior of wheel material under both dry and lubricated conditions. The main purpose of this research is to study the wheel-rail tribology for the Addis Ababa Light Rail Transit and to evaluate the friction and wear behavior of the wheel material under both dry and lubricated conditions. Composition, hardness, and ring compression tests were conducted to characterize the existing and the developed material. The percentage composition of carbon, manganese, and silicon gained 0.5%, 0.7%, and 0.25%, respectively, for existing and 0.8%, 1.15%, and 0.38% for alloyed wheel steel. It is also shown that the hardness value of the wheel material increased from 98.88 to 99.7 HRC when the existing material is compared with the developed material. The samples with dimensions outer diameter of 42 mm, inner diameter of 21 mm, and height of 14 mm were used for this study, and the dimensional change occurring under ring compression is different depending on the dry and lubricant conditions. Based on experimental analysis, 0.15, 0.13, and 0.09 were the evaluated coefficients of friction for dry, grease, and oil conditions, respectively. It is concluded that 0.09 is a coefficient of friction and oil is a suitable lubricant. To minimize wheel wear in the wheel-rail, proper lubrication and better application, improved wheel material, and revised track alignment for easier cornering and improvement are required. [ABSTRACT FROM AUTHOR]

Ceramic coatings have much potential for steel tubulars' protection against high temperature corrosion of gases and liquids, often containing abrasive solid particles, and to enhance their integrity in severe power generation, mineral and oil & gas production environments. Combining self-propagating high-temperature synthesis (SHS) with high-speed centrifugal process, alumina-based coatings were produced onto the inner surface of tubulars for these applications. According to the developed SHS batch formulation and the designed centrifugal device and process, well-consolidated composite ceramic layers with a thickness of 1.5–3 mm have been obtained. The developed SHS process does not create hazardous gases, and it takes ∼30 s for the ceramic phase formation. A high-level compaction due to centrifugal forces and a liquid phase sintering approach provided a dense gradient ceramic structure formed by oxide grains cemented by a glassy phase and bonded with a steel substrate through a thin iron layer. The coatings were successfully produced onto the inner surface of carbon and stainless steels' tubes of up to 12 ft-lengths and standard dimensions from 2 to 3/8″ to 7.5" OD. The coatings were tested, for the first time, in wear and high-temperature corrosive environments, e.g., in steam–H 2 S–CO 2 gases and molten salts, with encouraging results due to high contents of Al 2 O 3 and some other oxides and consolidated ceramic structure. They can be recommended for applications in high-temperature (900 °C and greater) corrosive environments and erosive flows. [ABSTRACT FROM AUTHOR]

In this research, hydrophobic polyester composites were made from cassava root cellulose (CRC) and twill-weaved banana fiber (TBF). The primary goal of this research was to develop a sustainable cellulosic material in micro dimension from the roots of the cassava plant and examine the load-bearing properties of composites made out of that. The cellulose-toughened banana fiber-reinforced unsaturated polyester composite was prepared using the hand layup method and cured in room temperature. It is observed that the load-bearing properties are improved with the addition of banana fiber and cellulose. The highest tensile strength of 137.3 MPa, flexural strength of up to 164.2 MPa, interlaminar shear strength of up to 5.87 GPa, Izod impact of up to 5.94 J, and hardness of up to 83 Shore-D were achieved for the composite made using 4 vol% of cellulose. Similarly, the composite had the lowest sp. wear rate of 0.011 mm3/Nm with COF of 0.171 for 4 vol% of cellulose addition. Moreover, all the composite designations were found to have a water absorption contact angle greater than 70°, indicating a retained hydrophobic nature. Scanning electron microscope (SEM) fractography demonstrated that 4 vol% CRC and TBF-reinforced polyester composites have superior bonding and durability. Finally, the thermal properties of composites revealed an improved set temperature of 424 °C in TGA as well as 82 °C in DSC for 4 vol% cellulose-added composite PCB3. These properties improved composites could be used in aerospace, automotive, military, and industrial sectors where higher mechanical strength, wear resistance, and hydrophobicity. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to develop lightweight polyester composites for possible application of human prosthetics. Since present materials in human prosthetics are either metals or synthetic harmful fibre and fillers, the present study proposes to introduce a new alternative biocomposite material for manufacturing human prosthetics. Thus, in this study, pineapple-basalt fibre sandwich with rice husk Si3N4 particle polyester composites was developed with two different staking sequences. The composites are prepared using the hand layup technique, and testing was carried out in accordance with American Society of Testing and Materials (ASTM) standards. The highest measured mechanical values for composite designation PBS1 up to 124 MPa, 162 MPa, 4.68 J, 21 MPa, and 79 shore-D for tensile strength, flexural strength, Izod impact, and hardness, respectively, when compared to all other composite designations. Corresponding to this, maximum fatigue life counts of 14,370 were seen for composite designation PBS1 with 1.0 vol. % Si3N4 particles included. However, the higher wear resistances value up to 0.007 for wear loss and 0.028 for co-efficient of friction (COF) for composite designation PBS2 resulted from the enhanced Si3N4 particle volume percentage up to 3.0 vol. %. The scanning electron microscope (SEM) fractography of the broken samples shows that the silane surface treatment has increased the interaction between the fibre and matrix phase. Thus, based on the present research, it is clear that the novel material structure (B/P/P/B) with pineapple/basalt fibre and Si3N4 is capable of replacing the existing man-made synthetic materials used in human prosthetic production with more advantageous attributes such as light weight, high strength, durable, abrasion resistance, and fatigue damage free. [ABSTRACT FROM AUTHOR]

The aim of this research was to prepare and characterise hybrid composites made with almond shell powder (ASP), palm kernel fibre and cardanol oil as reinforcing and toughening agents, respectively. The study intends to assess the composites' mechanical properties, wear resistance and antibacterial activity. ASTM standards were used to analyse the mechanical parameters, which included tensile, flexural, impact and compressive strength, hardness (shore-D). Results revealed that the addition of ASP to the composites resulted in a significant increase in tensile strength (E: 98 MPa, EC1: 91 MPa, EC2: 84 MPa, ECP: 126 MPa) due to its reinforcing effect. Furthermore, wear test (pin on disc) demonstrated that ASP inclusion reduced wear rates (E: 0.262, EC1: 0.288, EC2: 0.314, ECP: 0.281) greatly due to its abrasion resistance and strong lubrication effect. Cardanol oil, on the other hand, marginally increased wear rate, most likely due to its softening action and weakening of the composite's microstructure. The lowest sp. wear rate of 0.11 mm3/Nm was noted for composite ECPA2. However, at inhibition growth test, the cardanol oil–incorporated composites exhibited inhibitory zones against gram-positive and gram-negative bacteria, indicating that the composites' antibacterial activities were improved higher level. The microstructure and distribution of reinforcing components and cardanol oil inside the composite matrix were revealed by SEM examination. The findings of this work help to build sustainable and functional hybrid composites for a variety of engineering applications such as food packaging box manufacturing and domestic light weight and load applications including manhole covers, FRP hand rails and gratings. [ABSTRACT FROM AUTHOR]

AlCoCrFeNiTi0.5 high entropy alloy (HEA) coating with high hardness and excellent wear resistance was deposited on TC4 surface by electron beam cladding, and the process parameters, microstructure and properties of the coating were studied. The analysis shows that the microstructure of HEA coating is composed of dendritic (DR) and interdendritic (IR) phases. The IR phase, which is mainly composed of Fe and Cr, is confirmed to be BCC solid solution, while the DR phase is FCC solid solution with AlNi2Ti (or AlCo2Ti) structure. The grain orientation of the HEA coating is random, without obvious texture. Hardness gradually decreases from the upper part area of the HEA coating to the inner of the TC4 substrate. The hardness curve in the HEA coating region has some fluctuations, but the fluctuations are small, indicating a homogeneous microstructure. The average hardness of the HEA coating is 796.18 HV0.2, which is about 2.6 times that of the TC4 substrate. The HEA coating exhibits a higher coefficient of friction (COF) compared to the TC4 substrate. The average COF of HEA coating and TC4 substrate in the stable stage are 0.57 and 0.48, respectively. Wear loss of the HEA coating is 0.0657 mm3, about one tenth of that of TC4 substrate (0.6112 mm3). The hardness of the HEA coating is high, no obvious furrow is found, and its wear mechanism is considered to be a mixture of adhesive wear and oxidation wear. [ABSTRACT FROM AUTHOR]

Based on the characteristics of octopus arm suction cup shape and distribution, a laser cylindrical texture with dimensions of R = 500 μm, W = 200 μm, and H = 50 μm was designed on the surface of G20CrMo substrate material using laser surface processing technology. The grooves of texture were filled with SnAgCu and comparative tests were respectively conducted under dry friction and grease lubrication conditions with a loading force of 10 N, reciprocating frequency of 1 Hz, and stroke of 8 mm. A comprehensive characterization and parameter analysis of wear scars were performed using various material surface analysis instruments. The experimental results showed that the cylindrical textured surface filled with SnAgCu reduced the friction coefficient by 22.9% compared to G20CrMo substrate surface under the dry friction condition. In addition, under the grease lubrication condition, although the cylindrical textured unfilled surface resulted in a higher friction coefficient, the friction coefficient and wear loss of cylindrical textured surface filled with SnAgCu were respectively reduced by 18.6% and 60% compared to those of G20CrMo substrate surface. [ABSTRACT FROM AUTHOR]

In this research work, Al matrix is reinforced with graphene, synthesized by the powder metallurgy method, and further processed by the hot extrusion process. The microstructure of aluminum and Al-graphene composite samples was investigated using FESEM and optical microscopy. The grain structure is investigated to analyze the grain size of pure aluminum and aluminum-graphene composites. Pin on Disk wear test setup is used to investigate the tribological behavior of the developed composites. Developed samples were tested experimentally to evaluate the influence of graphene addition, applied load, and sliding velocity on wear behavior. From the results, the wear rate of Al-Graphene composites is observed to be lower compared to monolithic aluminum samples. However, wear rate increases with the increase in velocity of sliding and the applied load. The Coefficient of Friction (COF) of composite samples was less than that of pure aluminum samples. Results reveal that the graphene-Al composites exhibit superior tribological properties during tribological tests and exhibit a 38.1% reduction in wear rate at a 60 N load. [ABSTRACT FROM AUTHOR]