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In this article, lentils are used as a case study to characterise the particulate behaviour of soft granular materials. Experiments were carried out on a single lentil particle or a pair of lentils. The single particle or a pair of particles in contact were compressed vertically to crushing or to a fixed vertical load. Then, in inter-particle tests, pairs of particles were slid over each other at a constant vertical load, and the tangential stiffness and coefficient of friction were estimated. The pairs of lentil particles in contact were also subjected to repeated normal and tangential loading. The presence or absence of the cover of lentil particles (shell) was found to affect their behaviour significantly under these loading conditions. The lentil particles have a very compliant shell and stiff core in normal loading; the stiffness of the shell is constant, and the core follows Hertz contact law. The lentil particles show less variability in their crushing strength, with high Weibull modulus (~ 10), in comparison to other natural granular materials like sand. With repeated cycles of vertical loading, the contact between a lentil pairs of particles becomes more stiff and less damp. In tangential loading, the coefficient of friction between lentil particles decreases with normal force while the contact stiffness increases. Further, in cyclic tangential loading, the coefficient of friction decreases and the contact stiffness increases with cycles. A simple contact model is also proposed to use in discrete element simulations. [ABSTRACT FROM AUTHOR]

In sugarcane cultivation, operations from sowing to harvesting are critical and time-consuming. The lack of manual labor poses risks and increases drudgery, necessitating mechanization based on the engineering properties of 10–12 month old sugarcane stalks. Engineering properties of three sugarcane varieties (CoLk 14201, CoLk 09204 and CoPk 05191) from IISR Lucknow were evaluated. These properties are essential for designing effective machinery components. The average sugarcane stalk length and weight across three varieties were 2096 mm and 1.03 kg, with average diameter of 23.48 mm (bottom), 25.38 mm (middle) and 24.13 mm (top). Three-budded setts were longest and heaviest, followed by two-budded setts, with single-budded setts being the smallest and lightest. Setts length ranged from 55 to 354.5 mm, weight from 28.37 to 207.38 g and diameter from 15 to 29 mm. Optimal moisture content for setts was 70–75%, with values ranging from 67.57 to 83.33%. Bulk density varied between random and aligned storage, from 0.231 to 0.491 g/cm3 and 0.348 to 0.597 g/cm3, respectively. Coefficients of friction were highest with rubber and lowest with FRP. CoLk 09204 had the highest friction across all setts, while CoPk 05191 had the lowest, with vertical orientations showing higher friction. Penetration resistance increased from top to bottom internode segments, with CoLk 09204 showing the highest resistance (8.02–9.88 N/mm2). Cutting resistance was highest at the bottom stalk position, with CoLk 09204 having the greatest resistance (3.5 N/mm2). Crushing resistance was significantly higher in CoLk 09204 (1742–1787 N) and it also exhibited the highest bending resistance (1414.06 N/mm2), indicating a denser, more resistant stalk structure. These findings are essential for optimizing various sugarcane cultivation machinery components and processing methods. [ABSTRACT FROM AUTHOR]

Ejection is the most critical phase in the injection moulding process and depends on several variables that can affect and difficult the demoulding process. Some phenomena in the mould, such as shrinkage, adhesion and friction, can lead to higher ejection forces. Friction, deformation and adhesion mechanisms are components of the coefficient of friction that occurs between the mould and the part surface. An increase in the coefficient of friction will result in higher ejection forces and consequently increase the energy consumption during the demoulding process. Mould and part material, mould surface roughness, coatings and ejection temperature are some of the variables that can affect the coefficient of friction in the injection moulding process. This review paper presents some considerations on the mechanisms, the process and material variables that can affect the coefficient of friction. [ABSTRACT FROM AUTHOR]

The tribological behavior of silicon nitride (Si3N4) ceramic with textured patterns under water lubrication was investigated in this paper. Different textured patterns were fabricated using laser surface texturing (LST). Surface wettability was characterized by contact angle. The original surface and textured Si3N4 ceramic with triangular patterns presented as hydrophobic. However, the textured Si3N4 ceramic with hexagonal patterns presented as hydrophilic. Surface wettability and textured patterns were important factors affecting the friction performance of the Si3N4 ceramic. Our results indicated that symmetrical textured patterns were more beneficial for decreasing the coefficient of friction (COF) at lower reciprocating frequencies. In contrast, better surface wettability played a more important role in reducing the COF at higher reciprocating frequencies. The most severe damage observed on the untextured Si3N4 ceramic led to a higher wear rate. The symmetrical structure of hexagonal patterns was more conducive to decreasing the wear rate than triangular patterns. However, the Si3N4 ceramic with triangular patterns was more suitable for use at high-speed frictions due to better lubrication. The textured patterns had the function of storing lubricants and capturing and cutting debris. Thus, friction performance was improved by introducing textured patterns onto the surface of the Si3N4 ceramic. The friction and wear mechanisms are also discussed in this study. [ABSTRACT FROM AUTHOR]

Nitriding is a well-known thermochemical treatment improving the surface hardness and the wear resistance of steel. The phase composition and growth kinetics of the nitrided layer can be controlled using a gas nitriding with changeable nitriding potential. In this work, such a gas nitriding was used to produce, on 42CrMo4 steel, the two nitrided layers differing in the thickness of compound zone and diffusion zone. The microstructure and nanohardness of these layers were studied. For the first time, the tribological behavior of gas nitrided layers at elevated temperatures (from 23 to 400 °C) was investigated. The compound zone consisted of ε + (ε + γ') iron nitrides and, in the diffusion zone, the nitric sorbite with γ' precipitates was observed. The highest nanohardness was measured in the ε + γ' zone. The lowest values of friction coefficients were obtained if the contact surface of the friction pair entered the ε + γ' zone. After the wear process, at a final temperature of 400 °C, worn surfaces showed only intensive abrasive wear, evidenced by shallow grooves. The increased oxygen content at the edges of wear tracks indicated possible oxidative wear. [ABSTRACT FROM AUTHOR]

Yttria-stabilized zirconia and flake graphite c omposite (C/YSZ) coatings were successfully prepared on a TC4 substrate by electrophoretic co-deposition and sintering at 1100 °C using YSZ nanopowder and flake graphite. The effects of the graphite content on the microstructure and friction-wear properties were investigated. The results indicated that flake graphite agglomerated in the C/YSZ coating. The YSZ coating with 0.6wt.% graphite exhibited the highest toughness with the plastic resistance index (H/E) of 0.0172, which was 6.8 % higher than that of the YSZ coating, and effectively inhibited the formation of coating cracks. However, an increase or a decrease in the graphite content led to a decrease in the toughness of the C/YSZ composite coating. The agglomerated graphite in the C/YSZ composite coating acted as a solid lubricant and affected friction and wear properties. The coefficient of friction (COF) of the 0.6C/YSZ sample was 0.45, which was 40 % lower than that of the YSZ sample. The reason for this was that graphite effectively inhibited the falling-off of debris from the coating surface and reduced abrasive wear. However, an excessive amount of graphite, i.e., in case of the 0.8C/YSZ coating, decreased the roughness of the wear surface, leading to a reduction in the H/E and COF by 24.4 % and 29.7 %, respectively. [ABSTRACT FROM AUTHOR]

Recently, lightweight nanocomposite materials were mostly preferred in automobile sliding parts such as bushes, clutch plates, piston pins, brake shoes, bearing races, and cylinder liners subjected to tribological failures plays a vital role. This study aims to investigate the impact of utilizing Multi-walled carbon nanotubes (MWCNTs) and Silicon dioxide (SiO2) in equal proportions, with weight content variations of 0%, 1%, and 2%, in a polymer reinforced with natural basalt and synthetic glass fibers. The investigation will be conducted using a pin-on-disc wear test apparatus under dry sliding conditions, following ASTM standards. Three nanocomposite laminates were fabricated by manual layup method through the ultrasonication and magnetic stirring process Box-Benkhen Design (BBD) is employed to design experiments involving four input variables: filler content, load applied, distance of sliding, and velocity of sliding. The Response Surface Methodology (RSM) technique was employed to analyze the tribological properties. The study employed the Analysis of Variance (ANOVA) technique to identify the primary factors and construct regression mathematical models for output responses. The results showed that the minimum friction coefficient and specific wear values were 0.159 and 0.0002 mm3/Nm, respectively, when employing a 1% filler weight, load applied 20 N, distance sliding 1000 m, and velocity of sliding 1 m/s. The minimum filler content, friction coefficient, and specific wear rates exerted the greatest influence followed by other factors. [ABSTRACT FROM AUTHOR]

Aluminium-carbon nanotube (Al-CNT) composites have proven to offer a lot of potential for applications involving friction and wear. This study investigated the wear behaviour of Al-CNT composites with uniformly dispersed CNTs without structural damage at concentrations of 0.5 wt%. The wear behaviour of these composites has been compared with that of pure aluminium, which was fabricated using the identical wet shake mixing, compaction, and extrusion procedure. The study aimed to determine how CNT concentration and applied stress influence the wear behaviour of composite materials. Scanning electron microscope (SEM) was used by the researchers to examine the surface features of the worn samples. The study showed a significant increase in hardness and wear resistance with adding CNT. Compared to pure aluminium, the composite containing 0.5 wt. % CNTs demonstrated a 25% reduction in wear rate, and the average value of the coefficient of friction (µ) also decreased. The wear rate and coefficient of friction increased when samples containing 0.5 wt. % CNTs were subjected to various loading scenarios. The major contribution of CNTs to improving wear characteristics was discovered through SEM investigation of these worn surfaces. Using the ANSYS Workbench, a built finite element model was used to perform contact analysis on the disc and pin. Analytical results and experimental data were contrasted, and the ANSYS data was utilised to assess the process parameters. The comparison confirmed the analysis accuracy and dependability, which showed a consistent agreement between the analytical findings and the experimental results. [ABSTRACT FROM AUTHOR]

Exploring ways to improve the performance of rotating bands is of great importance for enhancing the power of modern artillery. This study prepared graphene oxide-coated Nylon (GO-Nylon) and Nylon samples based on nylon rotating bands in artillery systems to investigate the feasibility of introducing GO-coated nylon rotating band materials to enhance their tribological and thermal properties. The friction behavior and thermal effects of these two surfaces were analyzed under different external loads and surface roughness conditions. The results show that the excellent thermal conductivity of GO effectively reduced temperature accumulation during friction. Under an external load of 8 N, the surface temperature of GO-Nylon decreased by 14% compared to the Nylon surface, and the coefficient of friction (COF) decreased by 21%. At the same time, a simulation model was established, and its calculation results were consistent with the experimental trends, providing a further explanation of the experimental phenomena. This research provides a basis for the application of graphene-based coatings in the defense industry and presents new ideas for the development of high-performance rotating band materials. [ABSTRACT FROM AUTHOR]

Understanding the contact behaviour of slewing-ring thrust ball bearings is essential for accurate predictions of load distribution and evaluations of static and dynamic load capacity. Applying Hertz's theory to non-standard slewing ring bearings presents unique challenges due to their complex geometries and difficulties in achieving uniform surface finishes, leading to significant deviations from actual stress. This study addresses these limitations by comparing experimental results, numerical results, and the Hertz theory. The analysis considers three Hertz contact configurations between the bearing ball and the raceway. The results reveal significant deviations from the experimental values. To determine the cause of these variations, the friction coefficient between the ball and the raceway is determined using the gravitational method by varying the number of balls. Uneven load distribution across balls in slewing ring bearings under mechanical loads is exposed by friction coefficient measurement. To further explore, load-deformation experiments are conducted on the LMMB by placing varying numbers of balls and their positions. Results expose variations in load-taking behaviour among the balls, emphasizing the critical influence of contact area load distribution. [ABSTRACT FROM AUTHOR]

The objective of this work is to study the effects of Fe additions on the phase evolution, microstructure, and mechanical properties of heat-treated Ni(50-X)Ti50FeX shape memory alloys. The NiTiFe specimens were prepared by mechanical alloying, compaction, sintering, and heat treatment processes. The microstructural and phase analysis of the sample shows the NiTiFe phase along with Ti-rich and Ni-rich phases. Better mechanical properties were observed in 4 at.% Fe samples owing to the presence of secondary intermetallic phases such as Ti2Ni, Ni3Ti, Fe3Ti, and Ni4Ti3 compared to other samples. The 10 at.% Fe samples containing a higher percentage of NiTi(B19') and FeTi phases showed better shape memory behavior while showing a higher coefficient of friction as compared to other samples. Wear tests were done to determine the wear mechanisms prevalent during the tests. It was found that the adhesive and the abrasive wear were the most common mechanisms that contributed to the wear behavior of the sample. [ABSTRACT FROM AUTHOR]

The purpose of this investigation is to see how varying percentages of Graphene Nanoplatelets (GNP) affect the wear behaviour of carbon fibre reinforced epoxy (CFRE) composite. The hybrid nano composites were developed using hand layup process followed by compression moulding. Furthermore, the impact of operational parameters such as load and abrading distance against SiC paper of 220 grit size at a rotational speed of 200 rpm was investigated. It was found that incorporating a considerable amount (up to 0.5 wt. %) of GNP significantly improved the wear performance of CFRE composites. There is increase in wear loss again for 0.75 and 1.0 wt. % GNP. The morphology of developed nano hybrid composites were linked to data patterns on wear volume and specific wear rates. GNP addition up to 0.5 wt. % strengthened the fibre-matrix interface, preventing simple fibre pull-out from matrix/fillers and enabling increased wear resistance, according to worn surface characteristics investigation. [ABSTRACT FROM AUTHOR]

A comparative study of the temperature stability of a full-formula motor oil, Mobil Ultra SAE 10W-40, doped with two carbon nanoadditives (nanotubes and fullerenes) is presented. The optimum concentrations of the compared nanoadditives in terms of friction coefficients, as well as the optimum concentrations in terms of the amount of heat released during friction, have been preliminarily established. It was found that doping the studied oil with fullerene increases the critical temperature by 10–15°C, and alloying this oil with carbon nanotubes increases the critical temperature by 20–25°C. [ABSTRACT FROM AUTHOR]

This research investigated the tribological performance of phosphonium-based ionic liquid Tri hexyl tetra decyl-phosphonium bis (2, 4, 4-trimethylpentyl) phosphinate (IL) when used as an additive at a concentration of 1wt% to Cotton seed oil (CSO), Rattan Jot oil (RJO), Waste Cooking oil (WCO) and Polyalphaolefin (PAO) at different operating conditions. The results were compared with conventional PAO base oil. The tribological performance of all lubricants was studied using a Vertical Universal Testing Machine (MMW1A) and wear scar diameter were measured using an electronic microscope OLYMPUS DX-1000. The results indicated that the addition of ionic liquid further enhanced the tribological performance in terms of wear for all bio-lubricants except for waste cooking oil. However, the addition of ionic liquid does not have much effect on the tribological performance of PAO. Rattan Jot oil was found to have the best tribological properties with the addition of ionic liquid.

Abstract We used a neuromusculoskeletal model of bipedal walking to examine the effects of foot–ground friction conditions and gait patterns on slip- and trip-induced falls. We developed three two-dimensional neuro-musculoskeletal models in a self-organized manner representing young adults, elderly non-fallers, and elderly fallers. We simulated walking under different foot-ground friction conditions. The static friction coefficient between the foot and the ground was varied from 0.05 to 2.0. Under low friction conditions, the three gait models demonstrated slip-induced falls. The elderly faller model experienced the most slip. This is because the RCOF was higher in the elderly faller model due to its short stride length but much smaller foot clearance. Under high friction conditions, only the elderly faller model demonstrated trip-induced falls. Based on the analysis using the margin of stability, the forward postural stability of the model gradually decreased under high-friction conditions, with the toe of the swing foot contacting the ground and subsequently falling forward. These results imply that there is an optimal coefficient of friction for the ground to prevent slip- and trip-induced falls by people with less stable gaits, which may provide new insights into the design of shoes and floor surfaces for the elderly.

Lightweight materials with better resistance to sliding wear are prominent candidates for automobile brake drums, clutch pads and cylinder block applications to facilitate fuel economy. This attempt is reserved to cater to materials with higher tribological quality needs. Less dense foamy pumice stone particles were involved in three different percentages (5, 10, and 15 wt%) to reinforce lightweight AZ31 Mg alloy. A stir-assisted squeeze casting technique was pursued to process the composite and refine the grain structure. A phase detection, elemental mapping and microstructure study were done through X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM), respectively. An experimental dry sliding wear scrutiny was administered using a pin-on-disc apparatus by considering: (i) ambient and elevated temperature environments and (ii) three different levels of loads. The results reveal a significant drop in wear loss and a frictional coefficient for 15% pumice-loaded composite than the base alloy. Post-wear examination acknowledges the fact that the ambient temperature wear is governed by adhesive-abrasive wear and high temperature is by abrasive wear mechanisms. Worn-out scrutiny authenticates the presence of oxide layers and their role in lubrication. A comparative study with previous works upholds the novel magnesium composite is the right candidate for the mentioned automobile applications.

This work studied spark plasma sintered Ti48Al48Cr2Nb2 alloy for their nanoindentation and wear properties. Results showed an improvement in nanoindentation properties of the compacts with an increase in holding time from 5min to 7.5min for the heating rate of 50°C/min and 100°C/min. X-ray diffraction (XRD) analysis showed the intensity of diffraction peaks of two major crystalline phases of Ti3Al2.25Nb0.75 and γ-TiAl. Scanning electron microscopy (SEM) images of sintered compacts possessed varied microstructures due to different sintering parameters. The nearly lamellar structure showed a good balance of yield stress and fracture toughness. Wear tracks SEM analysis revealed the worn surface morphologies and the sample sintered for 7.5 min at the eating rate of 50°C/min sustained the least damage evident by the shallow grooves and narrow wear track. Profilometer measurements revealed the wear track depth and width, confirming the degree of wear for the samples sintered at varied conditions.

With burgeoning considerations over energy issues and carbon emissions, energy harvesting devices such as triboelectric nanogenerators (TENGs) are developed to provide renewable and sustainable power. Enhancing electric output and other properties of TENGs during operation is the focus of research. Herein, two species (Nb2S2C and Ta2S2C) of a new family of 2D materials, Transition Metal Carbo‐Chalcogenides (TMCCs), are first employed to develop TENGs with doping into Polydimethylsiloxane (PDMS). Compared with control samples, these two TMCC‐based TENGs exhibit higher electric properties owing to the enhanced permittivity of PDMS composite, and the best performance is achieved at a concentration of 3 wt. ‰ with open circuit voltage (Voc) of 112 V, short circuit current (Isc) of 8.6 µA and charge transfer (Qsc) of 175 nC for Nb2S2C based TENG, and Voc of 127 V, Isc of 9.6 µA, and Qsc of 230 nC for Ta2S2C based TENGs. These two TENGs show a maximum power density of 1360 and 911 mW m−2 respectively. Moreover, the tribology performance is also evaluated with the same materials, revealing that the Ta2S2C/PDMS composite as the electronegative material presented a lower coefficient of friction (COF) than the Nb2S2C/PDMS composite. Their applications for energy harvesting and self‐powered sensing are also demonstrated. [ABSTRACT FROM AUTHOR]

The working conditions of tools during plastic working operations are determined by, among other things, temperature, loads, loading method, and processing speed. In sheet metal forming processes, additionally, lubricant and tool surface roughness play a key role in changing the surface topography of the drawpieces. This article presents the results of friction analysis on the edge of the punch in a deep drawing process using the bending under tension test. A DC04 steel sheet was used as the test material. The influence of various types of titanium nitride and titanium coatings applied on the surface of countersamples made of 145Cr6 cold-work tool steel was tested by means of high-intensity plasma pulses, magnetron sputtering, and electron pulse irradiation. The influence of the type of tool coating on the evolution of the coefficient of friction, the change in the sheet surface topography, and the temperature in the contact zone is presented in this paper. An increase in the coefficient of friction with sample elongation was observed. Countersamples modified with protective coatings provided a more stable coefficient value during the entire friction test compared to dry friction conditions. The electron pulse irradiated countersample provided the highest stability of the coefficient of friction in the entire range of sample elongation until fracture. The skewness Ssk of the sheet metal tested against the coated countersamples was characterized by negative value, which indicates a plateau-like shape of their surface. The highest temperature in the contact zone during friction with all types of countersamples was observed for the uncoated countersample. [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]

This study highlights the impact of low amounts of MoS2 quantities on composite performance by examining the effects of ultrasonication exfoliated MoS2 at different loadings (0.1–0.5 wt%) on the mechanical and tribological parameters of epoxy composites. Even at low concentrations, the ultrasonication and exfoliation procedures greatly improve the dispersion of MoS2 in the epoxy matrix, enabling its efficient incorporation into the tribofilm during sliding. Optimum mechanical properties were demonstrated by the MoS2/epoxy composite at 0.3 wt%, including a modulus of elasticity of 0.86 GPa, an ultimate tensile strength of 61.88 MPa, and a hardness of 88.0 Shore D, representing improvements of 61.5%, 35.45%, and 16.21%, respectively. Corresponding tribological tests revealed that high sliding velocity (10 N load, 0.2 m/s) resulted in a 44.07% reduction in the coefficient of friction and an 86.29% reduction in wear rate compared to neat epoxy. The enhanced tribological performance is attributed to the efficient removal and incorporation of MoS2 into the tribofilm, where it acts as a solid lubricant that significantly reduces friction and wear. Even though an ultra-low amount of filler concentration was added to the composite, a unique finding was the high MoS2 content in the tribofilm at higher sliding speeds, enhancing lubrication and wear protection. This study establishes that even ultralow MoS2 content, when uniformly dispersed, can profoundly improve the mechanical and tribological properties of epoxy composites, offering a novel approach to enhancing wear resistance. [ABSTRACT FROM AUTHOR]

In this work, a multi-response optimization technique has been used to optimize the process parameters considered while conducting the wear tests of fabricated particle-reinforced epoxy composites. The paper signifies the effect of CaSiO3 and WS2 particles reinforced epoxy composite’s performance at different filler wt.% (2 wt.% CaSiO3 and 1, 2.5, 4, 5.5 and 7 wt.% WS2 ), load (30-70 N), and sliding distance (400-2000 m) parameters that are considered while conducting friction and wear tests. Experiments were conducted on a pin-on-disc configuration using an L25 OA through Taguchi's design of experiment for a constant time of 15 min. The results showed that the inclusion of particles improved the material's friction and wear resistance. The optimal combination of parameters was obtained with Taguchi-GRA followed by determining the most influencing factor using the ANOVA tool. The ANOVA tool calculates the percentage contribution of the process parameters. The wear behaviour was optimized to achieve the lowest coefficient of friction and specific wear rate. At a sliding distance of 2000 m and 15 min testing duration, the combination of parameters that yields the best result is a filler content of 2 wt. % CaSiO3 and 5.5 wt. % WS2, along with a load of 70 N. The ANOVA results reveal that the load with a percentage contribution of 50.87% is the most significant parameter followed by filler content (15.63%) and sliding distance (13.55%). A confirmation test is carried out using the optimal control parameters to validate the experimental results. Additionally, the SEM was used to analyse the worn surfaces of epoxy composites. The SEM images reveal the adhesive and abrasive wear mechanism is most prevalent in the observed material. [ABSTRACT FROM AUTHOR]

In recent years, plastic and metal 3D printing has experienced massive development in the professional and hobby spheres, especially for rapid prototyping, reverse engineering, maintenance and quick repairs. However, this technology is limited by a number of factors, with the most common being the cost and availability of the technology but also the lack of information on material properties. This study focuses on investigating the material properties of PLA, PETG, HIPS, PA, ABS and ASA in order to elucidate their behavior in terms of wear and thermal resistance. The research builds on previous studies focusing on the mechanical properties of these materials and includes wear testing and DMA analysis. Weight loss, frictional forces, and frictional work including relative frictional work are recorded as part of this testing. The storage modulus and loss modulus including tan(δ) were then measured using DMA. [ABSTRACT FROM AUTHOR]

The tribological performance of carbon-reinforced acrylonitrile butadiene styrene (ABS) composites is very important in determining their suitability for advanced engineering applications. This study employs response surface methodology (RSM) to evaluate the effects of printing temperature and post-processing annealing on the wear resistance and frictional properties of these composites. A central composite design is used to systematically explore the interaction between these two factors, enabling the development of predictive models for key tribological parameters. The results reveal that both the coefficient of friction (COF) and wear are affected by printing and annealing temperatures, although in a non-linear manner. Moderate printing temperatures and lower annealing temperatures were found to reduce friction and wear, with annealing temperature having a more pronounced effect on wear. To further optimize these responses, the desirability approach was applied for predicting the optimal conditions. The optimal combination of input parameters for minimizing both COF and wear was found to be a printing temperature of 256 °C and an annealing temperature of 126 °C. This research provides valuable insights for optimizing additive manufacturing processes of carbon-reinforced ABS composites, contributing to enhanced material durability in practical applications. [ABSTRACT FROM AUTHOR]

The accurate determination of static coefficients of friction (COFs) is crucial in engineering design, yet standard reference values often show considerable variability. As a result, engineers frequently need to perform experimental COF measurements to ensure the reliable transferability of model-based COFs to real-world components. However, the effectiveness of cost-efficient laboratory tests, typically conducted on standardized samples, in reflecting actual component performance is often questioned as it is not trivial to transfer and scale the tribosystem. This study addresses this issue by conducting friction coefficient experiments on interference fits and flange connections, comparing the results with laboratory-based COF tests. The findings reveal a strong correlation when the tribological conditions of the real assembly are replicated in the lab. This research offers a method to enhance the accuracy and transferability of COF values from lab tests to practical applications, providing engineers with a more reliable approach to friction testing. [ABSTRACT FROM AUTHOR]

In view of the low bract removal and high corn ear damage in the operation of the current peeling device, this work aimed to accurately measure the coefficients of friction (COFs) involved between peeling rollers and corn ears during the corn peeling. Consequently, the movement state of corn ear in a peeling device and the friction behavior involved were analyzed, and the mechanical model was established. Friction tests were conducted by using the modified tilting table, the modified direct shear apparatus, and the self‐built rolling friction apparatus. The value range and change rule of the COFs between corn ears and peeling rollers were obtained. Linear regression models were described for the COFs depending on moisture content. The results show that the coefficient of static friction (COSF) was 0.391–1.396, the coefficient of sliding friction (CODF) was 0.398–1.318, and the coefficient of rolling friction (CORF) was 0.119–0.377. All COFs were positively correlated with moisture content. Besides, the COFs of two rubber rollers were significantly larger than that of the steel roller. Among the two rubber rollers, the COFs were higher between the fish scale rubber roller and bare corn ears and were lower between the fish scale rubber roller and corn ears with bracts. This meant that the fish scale rubber roller was more likely to cause seed damage under the same conditions. Knowledge concerning these coefficients is believed to provide data support for the improvement and optimization of corn peeling devices. [ABSTRACT FROM AUTHOR]

Epoxy chip seals are widely used to improve the skid resistance of cement concrete pavements, which is significantly affected by surface texture. However, current methods for characterizing the surface texture structure are not precise, and the standard is not uniform. Therefore, a high-toughness modified epoxy resin chip seal structure was developed to conduct an indoor accelerated abrasion test. The elevation data of the epoxy chip seal under different abrasion times and different abrasion loads were obtained using laser scanning, and the Density/Sharpness combination parameters were obtained using the Hilbert–Huang transform and spectral analysis. The correlation between the texture parameters and the dynamic friction coefficient was analyzed using a stepwise multivariate quadratic polynomial method. The results showed that the texture structure of the epoxy chip seal surface is positively distributed, and the macroscopic texture occupies 49.45%, while the probability of the microscopic texture is only 4.55%. Meanwhile, the correlation coefficient between the texture parameters and the dynamic friction coefficient is 0.9307, which demonstrates that the selected texture parameters discard the texture components unrelated to skid resistance performance and reflect the distribution of the pavement texture and the skid resistance performance well. [ABSTRACT FROM AUTHOR]