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Squaring, a wood transformation process, is an operation which consists of introducing the logs into a squaring machine which then uses sharp tools to cut the wood into pieces with high surface quality. Tool steels used in this process experience significant wear, damaging the wood surface and hence leading to substantial scrape rate. This study investigates the wear resistance of three tool steels specifically designed for wood cutting applications: modified AISI A8, modified steels with 0% and 1% tungsten, and powder metallurgy prepared W360 steel. Furthermore, the influence of a PVD coating on the wear resistance of the three alloys was investigated. ASTM G65 abrasive wear tests were conducted using the dry sand/rubber wheel abrasion test. A methodology using a non-contact 3D measurement system and specialized software was developed, allowing for a thorough quantitative assessment of the wear of these steels. The results revealed that the coated A8mod + 1%W steel exhibits the best resistance among the coated steels. Despite the excellent intrinsic resistance of W360 steel, the coating did not provide a significant improvement for this steel, showing only a 10% reduction in wear. Microstructural analysis revealed that the predominant wear mechanisms were abrasion and impact. The relative performance of each steel was quantified and is reported. Field trials conducted under actual cutting conditions, indicate the superiority of W360 steel in terms of resilience to wear and impacts compared to other tested alloys, while confirming the effectiveness of surface treatments in mitigating material wear. However, A8 steel modified with 1% tungsten exhibits increased wear under coating.

Incorporating Cu and Zn into Mg as a biomaterial offers a unique opportunity to exploit their antibacterial performance and biodegradability. The main challenge in this area is understanding the ratio and effects of these elements. To achieve this, the present work, based on two separate studies, aims to develop a regression model and apply machine learning (ML) to predict the wear behaviors using the effects of Cu and Zn elements doped into Mg matrix at low ratios on wear and micro and nanostructure properties (Grain size, density, hardness, Crystallite Size, microstrain, dislocation density). The wear behavior of the samples was investigated under 5–20 N loads at a constant sliding speed of 42 mm/s. Auto Sklearn library was used to generate training models that accurately predict the wear loss, friction coefficient, and specific wear rate values. The model showed satisfactory explanatory power and reliability in predicting the volume loss target. It also exhibited remarkable capability in predicting the friction coefficient and specific wear rate targets. The results of sample wear tests (MgZn2 under 15 N) conducted to generate data not included in the dataset showed a high degree of agreement with the ML results. Sensitivity analyses confirmed that Load, Environment, Hardness, and Grain Size are the most influential factors in predicting wear behavior, further validating the model’s reliability and interpretability.

Due to increasing environmental concerns, there is growing interest in sustainable natural fiber-based hybrid composites. However, these materials face significant challenges across various fields and applications. This study aims to enhance jute-palmyra fiber-reinforced epoxy hybrid composites by incorporating nano-silica particles. The research investigates the improvement of physical, mechanical, and tribological characteristics of the composites with functionalized silica nanoparticle concentrations ranging from 0 % to 4 wt.%. Results show that increasing SiO 2 content enhances the composite’s density. Specifically, the composite with 3 wt.% SiO 2 exhibits the highest flexural strength (71.20 MPa), while 2 wt.% SiO 2 demonstrates superior tensile strength (55.52 MPa), impact resistance (4.02 J), and hardness (36 HV). Dry sliding wear tests using an L16 orthogonal array design reveal that hybrid nanocomposites with 2 wt.% SiO 2 display superior wear resistance under specified conditions. These findings underscore the significant performance advantages of SiO 2 -natural fiber hybrid composites, highlighting their potential in sustainable material applications.

The present study investigates the dry sliding wear behaviour of pure Zn, Zn–3Mg, and Zn–3Mg–0.5Y biodegradable alloys using mass loss measurements, friction torque monitoring on an Amsler tribometer, and optical profilometry of wear tracks. The microstructure of the Zn–Mg–Y alloy exhibited an α-Zn matrix comprising Zn–Mg intermetallic constituents and dispersed Y-rich phases. Tribological testing at 20 N and 30 N revealed a marked enhancement in wear resistance for Zn–3Mg in comparison to pure Zn, attributable to matrix strengthening by intermetallic phases. Despite the stabilising effect of Y on the friction response, there was no consistent reduction in wear volume under higher loads. Surface investigations have revealed a multifaceted wear mechanism, characterised by a combination of abrasion, oxide tribolayer formation, and localised adhesion. The measured wear rates were found to fall within the range documented in the available literature concerning biodegradable Zn-based alloys, thereby confirming the experimental validity of the findings. In summary, Zn–3Mg exhibited the optimal equilibrium between friction stability and wear resistance under the examined dry sliding conditions. However, further research in physiological environments is necessary to evaluate its biomedical applicability.

This paper investigates the effect of nitrogen content on the tribological behavior of 316L (N) stainless steel at three different nitrogen levels: 0.07, 0.11 and 0.22 wt. percent. AISI 316L (N), an austenitic stainless steel, is the primary structural material used in sodium-cooled prototype fast breeder reactors (PFBR). Wear tests were conducted using a pin-on-disc tribometer, with a sliding velocity of 0.8 m/s and a normal load of 40 N, over a sliding distance of 1000 m. The experiments were carried out against an Inconel 718 counter face material at four different temperatures: room temperature, 200 °C, 400 °C and 550 °C. The dry sliding wear tests were performed in a vacuum of 10–6 torr to simulate wear in liquid sodium. The investigation covered the properties of the three grades of stainless steel, including microstructure, hardness, X-ray diffraction (XRD), specific wear rate, wear resistance and wear coefficient. This study also compared three different wear models a weight loss model, an ASTM model, and geometric models highlighting the reported anomalies. Scanning electron microscope (SEM) photographs of the worn surfaces were used to assess the severity and mode of wear. It was discovered that wear resistance decreases as temperature increases due to the material’s thermal softening, and that the stainless steel with 0.07 wt% nitrogen exhibited the best wear resistance among the tested compositions.

Pin-on-plate and pin-on-disk wear tests are typically used for assessing the wear behavior of a given material coupling and estimating its wear coefficient using the Archard wear law. This study investigates differences in the Archard law for pin-on-plate and pin-on-disk cases, particularly for flat-ended pins. Both analytical and finite element models of the two tests were developed, assuming a 21 N normal load and a 50π mm sliding distance. In pin-on-disk simulations three different distances between pin and disk axes were considered, i.e., 1.25–2.5–5 times the pin radius (5 mm). For the results, wear volumes, pressure and wear depth maps were compared. Some interesting aspects arose: (i) the rotational effect in pin-on-disk tests causes higher wear volumes (up to 13%) with respect to pin-on-plate tests: the nearer the pin to the disk axis, the higher the wear volume; (ii) a simple quadratic formula is defined to correct the wear volume estimation for pin-on-disk tests; (iii) pressure redistribution occurs with higher values closer to disk axis, opposite to the wear depth trend. Due to the high computational costs, only the running-in phase of wear tests was considered. Numerical strategies are currently under investigation to extend this study to the steady state phase.

Tooth enamel wear occurs because of daily mastication and occlusion. This study investigated the wear behavior of bovine teeth against aesthetic restorative materials in vitro. Abrader specimens were fabricated using four tooth-colored restorative materials (zirconia, lithium disilicate glass ceramic, dental porcelain, and resin composite), with bovine tooth enamel as a control. Flattened bovine tooth enamel was used as the substrate specimen. These materials were characterized by Vickers hardness tests and surface roughness measurements. Two-body wear tests between the abrader and substrate specimens were performed, and the worn topographies were evaluated using a contour-measuring instrument and 3D laser microscope. The restorative materials and bovine tooth enamel had similar surface roughness but different hardness and wear behaviors. Bovine teeth showed the largest wear in tooth–tooth contact as the abrader and substrate specimens. Compared to bovine teeth, zirconia, lithium disilicate glass ceramic, and dental porcelain showed greater hardness and less wear on their surfaces, and less substrate wear of the opposite tooth enamel. The lowest hardness resin composite showed intermediate wear on its surface, resulting in the lowest substrate wear. Accordingly, dentists should pay attention to the selection of restorative materials to reconstruct their morphologies owing to different wear behaviors.

Influence of Cu-Ni-Mo alloying on the wear characteristics of ADI (Austempered Ductile Iron) was studied. Additionally, its influence on the formation of NbC and VC layers (produced by means of thermo-reactive diffusion treatment TRD) on the ADI samples, and layer wear characteristics were investigated. Four ductile cast irons samples were used, the reference sample with no alloying and three others alloyed with Cu, Cu-Ni and Cu-Ni-Mo, respectively. For layer production, molten salt baths composed of sodium borate, aluminum and ferro-alloy (Fe-Nb or Fe-V), at 1000 °C during a 2-h treatment were used. Since the high TRD temperature was responsible for the austenitization of the sample, an austempering treatment direct from the TRD bath was performed immediately afterward using another molten salt bath at 300 °C. Sample examination and analysis were performed by optical and SEM microscopy, EDX, XRD, Brinell and Vickers hardness, Daimler-Benz Rockwell-C adhesion testing and fixed ball type micro-adhesive wear tests. TRD treatments were highly efficient in the production of robust uniform carbide layers with good adhesion to the substrates in all the samples. Wear resistance of the carbide layers was much greater than the austempered only substrates indicating the effectiveness of the TRD treatment for the materials studied.

In this study, the effects of milling time and heat treatment on microstructure and wear behavior of Cu-Al-Ni shape memory alloys produced by the mechanical alloying method were investigated. Cu-Al-Ni shape memory alloys were produced by mechanical alloying in four different durations (2.5, 5, 7.5 and 10 h) in a planetary-type mill. The produced Cu-Al-Ni shape memory alloys were characterized by microstructure (SEM + EDS), x-ray diffraction, thermal analysis (TG/DTA-DSC), and hardness, density, and dust size measurements. In the wear tests, three different loads (10, 20, and 30 N), five different sliding distances (400, 800, 1200, 1600, and 2000 m) and a sliding speed of 1 ms −1 were used. As a result of the studies, it was observed that the powder size decreased with the increase in MA time. It was observed that the density of heat-treated shape memory alloys decreased compared only to sintered alloys. According to the wear test, the lowest wear rate was obtained in Cu-Al-Ni shape memory alloys exposed to mechanical alloying for 7.5 h, with the highest hardness value. In addition, it was observed that the wear rates decreased in heat-treated Cu-Al-Ni shape memory alloys as the sliding distance increased.

Based on the velocity similarity theory, a test system for sediment wear flow around Francis turbine runner blades was established. The sediment wear test was carried out on the surface of Francis turbine runner blades with severe sediment wear before and after tungsten carbide spraying. The wear rate prediction model was established, and the effect of tungsten carbide spraying on the wear resistance of runner blades was analyzed. The results show that the serious wear position of Francis turbine runner blade by sediment appears in the head and tail, and the greater the load, the more serious the wear; after tungsten carbide spraying treatment, the sediment wear of runner blades is reduced by more than 90%, and the wear life is greatly improved. The sprayed tungsten carbide coating treatment is effective in reducing the effects of sediment wear.