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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]

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]

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]

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]

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]

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]

AbstractThe present study concentrates on the development of carbide-free bainite steel and explores its tribological and mechanical characteristics using a newly devised disk-on-disk tribometer. The microstructure of the treated samples was examined through heat treatment at various holding temperatures (300, 350, and 400 °C) and durations (10, 20, and 30 min), along with isothermal transformation. The wear rate demonstrated significant sensitivity to holding duration, transformation temperature, phase fraction, and the stability of retained austenite. The microstructural analysis encompassed atomic force microscopy (AFM), FE-SEM, x-ray diffraction (XRD), and energy-dispersive x-ray spectroscopy (EDS). The study extensively investigated the robust correlation among mechanical properties, microstructure, wear behavior, and the presence of retained austenite (RA) and bainite volume fraction. The findings indicate that carbide-free bainite steel holds promise for replacing conventional railway wheel track steel in the steel industry. The structural property correlations have developed of high silicon steel, hardness reduced with increasing temperature and isothermal preserving time; resulting in a gradual increase in the wear rate of CFB steel. The salt bath soaking temperature of 350 °C with a period of 30 min was found to be the preeminent wear properties condition for CBF steel. [ABSTRACT FROM AUTHOR]

The present work focuses on suggesting Gr as a valuable self-lubricating reinforcement for hybrid composite samples and offering a minimum wear rate for sliding pairs with fewer mechanical surface defects at the same time. A series of samples were fabricated using the route by stir casting method considering B4C and Gr as the two reinforcements. The morphology of the sample has been studied using the X-ray diffraction graphs, Energy dispersive X-ray analysis and Scanning electron imaging stating the homogeneity of reinforcement in various composite cast. The theoretical and experimental density of the series of samples has been studied and compared stating the low porosity of the samples fabricated. A maximum wear rate (Wr) of 0.351 × 10−4 mm3/m. was found for pure aluminium sample against EN31 steel disc with 0.053 as friction coefficient (µ). Wr was somehow seen to reduce up to 0.286 × 10−4 mm3/m for Al-B4C composite with µ of 0.48. For hybrid samples, the wear rate was further seen to improve to 0.187 × 10−4 mm3/m for Al-B4C and Gr 2.0% weight with µ of 0.38. Least Wr was found for composite having Gr 3.5% weight, of 0.149 × 10−4 mm3/m. with µ of 0.36. SEM images of the worn surface give evident results for delamination and crack formation on the pin face for the pure-Al sample. Taguchi-ANOVA analysis has been carried out showing the valid contribution of pin type, load and sliding speed on Wr and friction coefficient as the P-value lies below 0.05 for input parameters considering the 95% confidence level of the model developed. An F-value of 44.57 with R2 of 0.895 is developed for Wr model and an F-value of 54.2 with R2 of 0.934 for the µ model. [ABSTRACT FROM AUTHOR]

Laser cladding technology is an advanced surface modification technique that has gained significant attention in various fields due to its energy savings, efficiency, and environmental friendliness. This paper discusses the preparation of AlCoCrFeNi high‐entropy alloy (HEA) coatings on the surface of a 5083 aluminum alloy using laser cladding technology under the Ar gas conditions. An orthogonal test system was used to optimize the laser cladding process parameters. The microstructure, as well as the mechanical, frictional, and electrochemical properties of the HEA coatings, were comparatively analyzed under the two process conditions S4 and S10. The results indicate that, under S10, the HEA coatings exhibit optimal surface quality. The coatings contained a mixture of Face‐centered cubic (FCC) and Body‐centered cubic (BCC) phases. Microscopic examination revealed three distinct areas: dark, gray, and off‐white. The coatings can significantly improve the wear and corrosion resistance of the alloy substrate. For the best results, it is set the laser power to 200 W, the laser scanning distance to .05 mm, and the laser scanning rate to 1250 mm/s. This present study offers a novel technical foundation for the fabrication of HEA coatings. [ABSTRACT FROM AUTHOR]

Highlights In polymer‐based dental composites, wear is a three‐body wear system mainly abrasive, because of the food particles and wear products suspended in the oral cavity, which are transferred to the microcavities of the surface of the replacements. Due to this fact, the incorporation of nanodiamond as reinforcement in these polymer–matrix composites, which promotes the creation of a solid lubricant tribofilm surface could be advantageous. With the reinforcement of nanodiamonds, BisGMA/TEGDMA‐based composites increase their microhardness by 95%–420%. A maximum hardness exceeding 65 HV is achieved with a reinforcement of 3.2 wt%. The specific wear rate of neat BisGMA/TEGDMA is near 10−4 mm3/Nm and the Archard's coefficient is 2.6 × 105. The incorporation of a content of 1.6 wt% ND is enough to cause a diminution of ~78% in the friction coefficient and a reduction of the specific wear rate and Archard's coefficient of ~50%. Nevertheless, the addition of relatively high contents reduces the effectiveness of photoinitiation and photocuring, which is related to the scattering and absorption of light radiation by ND. This causes a significant decline in elastic properties starting at 50 μm from the surface. Photocuring polymer resin was successfully reinforced with nanodiamonds. Microhardness increases from 95% up to 420%, close to commercial composites. Friction coefficient and wear rate are reduced with 1.6 wt% nanodiamonds. High levels of reinforcement reduce the effectiveness of photocuring. [ABSTRACT FROM AUTHOR]

In this study, a small‐sized shredder machine equipped with spiral oriented double‐edged rotating and fixed blades was utilized to shred high‐density polyethylene (HDPE) waste. The performance of the shredder machine was determined based on the recycling and shredding efficiency, the percentage of retention, and the wear of its rotating and fixed blades. The wear of the blades was examined using an optical microscope, a scanning electron microscope, an energy dispersive x‐ray, and an x‐ray diffraction. High recycling (~95 %–98 %) and shredding (~66 %–70 %) efficiency, and low percentage of retention (~1.2 %–4.1 %) indicated a reliable performance of the shredder machine. The rotating blade exhibited higher wear at the back end, compared to the front end for the fixed blade. The wear of the blades was due to scratching and edge chipping. Formation of iron oxides during shredding did not cause significant changes in the hardness of the blades. Based on the evaluation, cost‐effective and time saving maintenance of the shredder blades could be achieved by gradual maintenance starting from the blade exhibited high wear. [ABSTRACT FROM AUTHOR]

As an essential mechanical component, a rolling bearing can exhibit multiple failure modes that may occur independently or in correlation with one another. A reliability analysis method that meticulously accounts for the interdependencies among various bearing failure modes is presented in this paper. The examination of wear and fatigue failure mechanisms in rolling bearings is carried out using the Physics of Failure (PoF) approach. By considering the influence of uncertain variables, the limit state functions for individual failure modes are formulated through the application of stress‐strength interference theory. In the context of wear failure, the limit state function is derived using working clearance as the characteristic quantity. On the other hand, the limit state function for fatigue failure is constructed with a focus on fatigue damage accumulation. The Copula function is used to characterize the relationship between wear failure and fatigue failure, and a reliability calculation model for rolling bearings is developed, considering the correlation between these failure modes. Ultimately, the proposed method is utilized to assess the reliability of bearings under two different sets of test conditions. The feasibility of this method is confirmed through test data, demonstrating its effectiveness in predicting bearing reliability. Through the application of this method, engineers can optimize bearing size parameters, select appropriate initial clearances, and enhance the reliability design of bearing. [ABSTRACT FROM AUTHOR]

Most recently, metro rigid overhead wire-pantograph systems are subjected to severe wear of overhead wires and current collectors throughout China, which are difficult to completely solve up to now. The severe wear of metro rigid overhead wire-pantograph systems is probably brought about by the medium-high frequency vibration of the metro rigid overhead wire-pantograph systems. Coincidentally, corrugation is frequently found in rigid overhead wire systems, but rarely in flexible catenary systems. A frictional self-excited vibration model of a rigid overhead wire-pantograph system was set up. The self-excited vibration characteristics were investigated using the transient analysis and the motion stability analysis. Results show that when the friction coefficient is greater than 0.07, the rigid overhead wire-pantograph system is more prone to self-excited vibration. The self-excited vibration frequencies cover a range of 20–1000 Hz. The simulated overhead wire corrugation approaches the measured corrugation in wavelength. The influence factor analysis displays that the friction coefficient, zigzag layout of rigid catenary wires, and sliding direction of pantographs have significant effects on overhead wire corrugation, and but the train speed, normal force, main spring stiffness, and span of two positioning clips have a little effect. [ABSTRACT FROM AUTHOR]

This article explores the properties of composite materials employed in dental fillings. A traditional nano-hybrid composite containing nanofiller particles exceeding 82% by weight served as a benchmark. The remaining samples were fabricated from ormocer resin, maintaining an identical nanofiller content of 84%. In all specimens, the nanoparticles were dispersed randomly within the matrix. This study presents findings from investigations into surface geometry, hardness, wettability, and tribological behavior. The microscopic observations revealed that ormocer-based samples exhibited greater surface roughness than those composed of the traditional composite. Hardness testing indicated that both ceramic addition and sample preparation significantly influenced mechanical properties. Ceramic-enhanced samples demonstrated superior hardness, surpassing the reference composite by 30% and 43%, respectively. Contact angle measurements revealed hydrophilic characteristics in the classic composite, contrasting with the hydrophobic nature of ceramic-containing samples. Tribological evaluations revealed the superiority of the classic composite in terms of friction coefficients and volumetric wear compared to ormocer-based materials. [ABSTRACT FROM AUTHOR]

(1) Objectives: This study investigated and compared the wear and flexural strength of two highly filled (injectable), one flowable and one paste composite. (2) Methods: Two highly filled flowable composites (G-aenial Universal Injectable and Beautifil Plus F00), a paste composite (Empress Direct) and a conventional flowable (Tetric EvoFlow) were tested. A two-body wear test was carried out using 10 disc-shaped samples from each group, which were subjected to 200,000 wear machine cycles to simulate wear, followed by Scanning Electron Microscope analysis. Flexural strength was tested using a three-point bend test using 15 beam samples for each of the four groups. Values were statistically compared using one-way analysis of variance (ANOVA) for flexural strength and a Kruskal–Wallis test for wear. (3) Results: The median volume loss for G-aenial Universal Injectable and Beautifil Plus F00 was statistically lower than that of both Empress Direct and Tetric EvoFlow. For flexural strength the two highly filled flowable composites both exhibited statistically higher mean flexural strength values compared to Empress Direct (p < 0.004) and Tetric Evoflow (p < 0.001). There were no statistically significant differences in the values of wear and flexural strength between the two highly filled flowable composites. (4) Conclusions/significance: Highly filled flowable composite resins with nano filler particles outperformed a conventional flowable and a paste composite resin in terms of wear resistance and flexural strength, and may be suitable to use in occlusal, load-bearing areas. [ABSTRACT FROM AUTHOR]

In this study, for the first time, the optimization of applied pressure for achieving the one of the best tribological properties of diamond-like carbon (DLC) coating on graphite surface using plasma-enhanced chemical vapor deposition (PECVD) method was investigated. Raman spectroscopy and microscopy methods were used to characterize the applied coating. Additionally, the mechanical properties of the coating were investigated through nanoindentation testing. The wear resistance of coating has been tested as functional test. The results indicated that with increasing gas pressure, the sp3 hybridization percentage decreases, while the ID/IG ratio increases. The average roughness values for the uncoated sample and the coated samples at working pressures of 25, 30, and 35 mTorr were obtained as 1.6, 5.1, 3, and 2.4 nm, respectively. The results of hardness and wear tests showed that these properties were optimized by reducing the applied gas pressure. The highest hardness was 11.59 GPa, and the best sample in terms of the mechanical properties of the coating was the sample applied at a gas pressure of 25 mTorr. Results show that the optimal sample in tribological performance is the one applied at a working pressure of 25 mTorr. Because this sample demonstrates the lowest coefficient of friction, and wear depth. [ABSTRACT FROM AUTHOR]

Ulexite and colemanite filled acrylonitrile-butadiene-styrene parts are manufactured by injection molding method. Tensile and wear tests are applied to reveal specific properties of composite parts. Various characterization methods are used to confirm the filler-matrix interactions, polymer melt flow, friction mechanisms, and fracture modes. This study investigated the use of ulexite and colemanite as fillers in acrylonitrile-butadiene-styrene composite parts, focusing on their impact on mechanical and frictional properties. Results showed that the addition of ulexite and colemanite fillers significantly improved mechanical properties such as compared to pure ABS, however ulexite filler showed much better performance compared to colemanite. In terms of wear test, ulexite filled ABS specimen showed a smooth wear while pure and colemanite filled ABS provided severe wear characteristics. These findings have implications for the development of high-performance composite materials for use in industries such as automotive and aerospace. [ABSTRACT FROM AUTHOR]

The current research work involves the fabrication and tribological properties analysis of constant basalt filler reinforced (30 wt %) bio-based polypropylene (PP) and high density polyethylene (HDPE) thermoplastic composites. Compression molding technique is used after an internal mixing process in order to produce composite samples. The physical and hardness properties have been evaluated for both neat polymers and composite samples. In order to study the coefficient of friction (COF) and specific wear rate (SWR) of PP and HDPE composite samples, the Taguchi and Analysis of Variance (ANOVA) methodologies were applied. For PP samples, the optimum parameters in response to COF are found to be 0 wt% basalt (rank 3), 9 N load (rank 1), 200 r/min speed (rank 4), and 100 m distance (rank 2); for the SWR output, the optimum parameters are 30 wt% basalt (rank 1), 6 N load (rank 4), 100 r/min speed (rank 2), and 200 m distance (rank 3). For HDPE samples, the optimum parameters in response to COF are 0 wt% basalt (rank 1), 6 N load (rank 3), 100 r/min speed (rank 4), and 100 m distance (rank 2); for the SWR output, the optimum parameters are 30 wt% basalt (rank 1), 6 N load (rank 3), 100 r/min speed (rank 4), and 150 m distance (rank 2). Consistently, it has been shown that incorporating basalt fillers to PP and HDPE composites has more dramatically decreased SWR than COF. The depth of wear constantly rises according to increasing load, irrespective of the processing variables, as shown in 2D depth profiles. It is discovered that the confirmation tests carried out for the optimum parameters are within statistically acceptable bounds. The depth profile plots revealed that the worn track edges are found with polymer bumps because of deep grooves and softened polymer debris, which commonly observed more with HDPE samples due to low softening temperature. Moreover, the worn surfaces of the composites have plowed lines and cracks that are brought about by the micro-cutting and micro-plowing activity of the erosive asperities counterface. In addition to surface characteristics, the transfer films created during sliding also significantly influenced the mode of sample wear. [ABSTRACT FROM AUTHOR]

In order to meet the needs of pinch rollers and prolong the service life, investigations were conducted on the Stellite delstain-442 built-up welding layers in use and the proposed replacement of Stellite Multipass-249 and Stellite Multipass-224HC built-up welding layers. The microstructure and fracture morphology of three different materials after different heat treatment temperatures were observed. The variations of high-temperature mechanical properties under different test temperature were compared. The results indicated that the brittleness of 249 and 224HC built-up welding layers was quite high and limited their applications in pinch roll system although the anti-wear properties and surface hardness of 249 and 224HC were superior relative to 442. For now, the comprehensive performance of 442 built-up welding layers was more suitable to be applied in pinch roll system, but further modifications on 442 built-up welding layers must be carried out to gain more excellent mechanical and anti-wear properties based on sacrifice of partial plasticity through composition regulation, microstructure regulation and optimization of heat treatment. [ABSTRACT FROM AUTHOR]

The present study investigated the effect of incorporating Yttria-Stabilized Zirconia (YSZ) and copper (Cu) in the development of Titanium-Based Metal Matrix Composites (TMCs) using the Friction Stir Processing (FSP) technique. The macrostructure of the TMCs, after adding 5% YSZ and 2% Cu, displayed a defect-free, crack-free, and porosity-free surface, indicating the precision of the FSP method. Microstructure analysis revealed a uniform distribution of reinforcement particles and proper dispersion of grains, key for enhancing mechanical properties. The interfacial bonding between titanium and YSZ was exceptionally strong, devoid of cracks and porosity, attributed to the copper additive's role. The increase in the number of grains per square inch for the Ti/5% YSZ/2% Cu composite (1176.26 grains per square inch at 500×) signified finer grain structure, contributing to a remarkable 48.04% improvement in tensile strength compared to pure titanium. The uniform distribution of reinforcement and strong bonding between titanium and YSZ are the driving forces behind the 46.34% increased in hardness. Additionally, the wear resistance of the composite improved by approximately 76.66%, a vital characteristic for applications facing abrasive conditions. The corrosion testing demonstrated an 8.33% enhancement in corrosion resistance with the Ti/5% YSZ/2% Cu composite. [ABSTRACT FROM AUTHOR]

In the recent study, accumulative roll bonding (ARB) and powder metallurgy processes are used as a combined technique to fabricate AA1050/TiC composite strips. Then, corrosion, mechanical, wear properties and microstructural evolution of them have been investigated via TiC Wt.%. All composite samples were fabricated after four cycles to get a uniform scattering of particles inside the metallic matrix. Moreover, density as a physical property and electrical resistivity and conductivity have been investigated vs particles value. The results showed that by increasing the particles value (Wt.%), hardness, density, corrosion and wear resistance of samples improved while their electrical conductivity, bonding strength and elongation decreased. For samples with 10 Wt.% of TiC and in comparison with the monolithic sample, the hardness and tensile strength of composite samples improved 127% and 63%, respectively. Finally, SEM morphology of worn and corrosive surfaces has been investigated. [ABSTRACT FROM AUTHOR]

To assess the effects of T5 and T6 heat treatments on the structural, mechanical, and tribological properties of Zn-40Al-2Cu-0.1Sr alloy several ingots were produced by the permanent mold casting. The structure and properties of the alloy were investigated by appropriate test procedures. It was observed that the as-cast microstructure of the alloy consisted of a dendrites, eutectoid transformation product of α+η phase mixture, copper-rich ε (CuZn4), and µ(SrZnx) phase particles. T5 heat treatment had no significant effect on the dendritic microstructure of this alloy but T6 heat treatment removed it completely. It was also observed that T5 heat treatment decreased the hardness and tensile strength but caused a slight increase in the elongation to fracture of the alloy. T6 heat treatment caused an increase in the hardness and tensile strength of the alloy but decreased its elongation to fracture. It was also observed that both heat treatments (T5 and T6) increased the wear resistance of the alloy. The effects of the heat treatments on the mechanical and tribological properties of the alloy were explained in terms of the observed microstructural changes. [ABSTRACT FROM AUTHOR]

The friction and wear of B 4 C ceramics with different contents of Al 2 O 3 /Y 2 O 3 sintering additives were studied under dry sliding. With the increase of Al 2 O 3 /Y 2 O 3 content, the friction coefficient of B 4 C ceramics decreases first and then increases, and the wear rate of B 4 C ceramics decreases gradually. The friction coefficient of B 4 C ceramics is related to the amount of wear debris generated on the sliding interface, which is determined by the competition between the number of pores that can trap the wear debris and the degree of grain pullout and grain fracture. When the content of Al 2 O 3 /Y 2 O 3 is 5 wt%, the amount of wear debris on the sliding interface is the least, leading to the lowest friction coefficient. The wear rates of B 4 C ceramics are controlled by the competition of the beneficial effect of improved relative density and mechanical properties and the adverse effect of weak bonding between B 4 C grains due to the formation of intergranular phase. The gradually decreased wear rate of B 4 C ceramics with the increased content of Al 2 O 3 /Y 2 O 3 is attributed to the improved relative density and mechanical properties. [ABSTRACT FROM AUTHOR]

This investigation employs the salt bath nitriding to extend the service life and improve the surface characteristics of AISI 52100, commonly employed in bearing applications. A wear test was conducted using a pin-on-disc device according to the ASTM G-99 standard, and the findings show a 30% reduction in wear loss. Sliding wear experiments were conducted at 1.5 m/s with a 5 N force at room temperature on uncoated and nitrided pins which was obtained as optimum value from RSM. The three variables and five levels of central composite design (CCD) were utilized to reduce the number of trials and the model relations were examined through ANOVA. Surface hardness, friction coefficient, wear coefficient, and loss in wear are measured over pins without coating and nitride pins. Investigations were done into how 5W30 oil affected passive and drip lubrication. Nitride substrates had a hardness of 590 HV. Also, nitriding has a favorable effect on the friction coefficient, lowering it by up to 23%. The 5W30 lubricant will further decrease the friction coefficient. The lowest friction coefficient was seen with the addition of 14% drip oil lubrication. Significantly less wear loss in the pin was caused by a combination of high hardness and low friction coefficient. [ABSTRACT FROM AUTHOR]

Ti-Ta coatings were deposited on titanium alloy by electrospark deposition in the anode mixture of titanium granules and tantalum powder in an argon atmosphere. The cathode weight gain kinetics, tantalum concentration, structure, oxidation resistance, microhardness, and tribotechnical properties of the coatings were studied. It was shown that, with increasing tantalum concentration in the anode mixture, the net cathode gain during 10 min of treatment increased monotonically. The average thickness of the deposited coatings varied in the range from 30.9 to 39.1 µm. The concentration of tantalum in the coating composition increased with increasing tantalum powder concentration in the anode mixture. The coating structure was dense without longitudinal and transverse cracks. With an excess of tantalum powder in the anode mixture, the discharge energy was not enough to completely melt it. The phase composition included α-Ti and a bcc tantalum solid solution in β-Ti. With increasing powder concentration in the anode mixture, the intensity of the bcc-phase peaks increased relative to the α-Ti peaks. The surface hydrophobicity of Ti-Ta coatings was higher than that of uncoated Ti6Al4V titanium alloy. The developed method can be used to produce Ti-Ta coatings with up to 5.9 times higher oxidation resistance compared to Ti6Al4V alloy. The high oxidation resistance of Ti-Ta coatings is explained by the formation of a dense and durable TiO2 layer. The surface microhardness of Ti-Ta coatings ranged from 4.72 to 4.91 GPa. The friction coefficient was in the range of 0.87–0.97. The wear resistance was 23 to 36 times higher as compared to the titanium alloy. [ABSTRACT FROM AUTHOR]

The present study adopts a multi-facet approach to design bio inspired concentrated alloys for potential application as articulating surfaces in joint replacements. A series of equiatomic, Nb rich and Ti rich TiMoNbZr based medium entropy alloys (MEAs) were processed via arc melting and their mechanical, in-vitro corrosion, wear, and in vitro and in vivo biocompatibility were investigated. Equiatomic MEA had primarily bcc with minor hcp phases where the single bcc was achieved with the addition of Nb. The single bcc Nb rich alloy resulted in 13 % elongation, much higher than equiatomic or Ti rich alloy. All the MEAs showed comparatively higher yield strength due to the climb of edge dislocations which is the main rate limiting mechanism at 300 K, as evident molecular dynamics (MD) simulation. The locally fluctuating energy landscape promotes kinks on edge dislocation, and at local minima nanoscale segments gets pinned. Upon yielding the entangled kink leaves a trail of vacancies/interstitials and escapes via climb motion to render high yield strength. The higher corrosion and pitting resistance of Nb enriched alloys can be attributed to the stable ZrO 2 , Nb 2 O 5 , TiO 2 , and MoO 3 oxides, high polarization resistance (106–105 Ωcm−2), and low defect densities (1016–1018). In vitro cell-materials interaction using MC3T3-E1 showed bioinert but cytocompatible nature of the MEAs. The wear rate of the MEAs was in the range of 7–9 × 10−5 mm3N−1m−1. The wear debris did not show any tissue necrosis when implanted in rabbit femur rather new bone regeneration can be seen around the particles. In the present work, a noble Nb enriched MEAs with superior mechanical, in vitro wear, corrosion and cytocompatibility properties was designed for articulating surfaces in joint replacement. • Single bcc in Nb enriched MEAs resulted in 13 % elongation with high hardness and yield strength. • Climb of entangled edge segment is the rate limiting mechanism in controlling high yield strength of MEAs at 300 K. • High polarization resistance (106–105 Ωcm−2), and low defect densities (1016–1018) attributes to ZrO 2 , Nb 2 O 5 , TiO 2 , and MoO 3 oxides enriched passive film. • Wet sliding wear rate ranged in order 7–9 × 10−5 mm3N−1m−1. In-situ generated wear debris when implanted in rabbit femur did not show any tissue necrosis rather new bone regeneration was observed around debris. [Display omitted] [ABSTRACT FROM AUTHOR]