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The purpose of this paper is to investigate the tribological properties of the WC/TiC-Co substrate under different loading conditions under three impact abrasive wear conditions.

The three body collisional wear behavior of Co alloy with WC and TiC at three impact energy was studied from 1 to 3 J. Meanwhile, the microstructure, hardness, phase transformation and wear behavior of these specimens were investigated by scanning electron microscopy, Rockwell hardness (HRV), EDS and impact wear tester. The resulting wear rate was quantified by electronic balance measurements under different pressures.

The specific wear rate increases with the increase of the nonlinearity of the impact energy and the increase in the content of WC or TiC. The effect of TiC on wear rate is greater than that of WC, but the hardness is smaller. The wear characteristics of the samples are mainly characterized by three kinds of behavior, such as cutting wear, abrasive wear and strain fatigue wear. The WC-Co with fewer TiC samples suffered heavier abrasive wear than the more TiC samples under both low and high impact energy and underwent fewer strain fatigue wears under high impact energy.

The experimental results show that the wear resistance of the Co alloy is improved effectively and the excellent impact wear performance is achieved. The results can be used in cutting tools such as coal mine cutting machines or other fields.

This study explores how titanium oxide (TiO₂) filler influences the specific wear rate (SWR) in flax fiber-reinforced epoxy composites (FFRCs) through a Taguchi approach. It aims to boost abrasive wear resistance by incorporating TiO₂ filler, promoting sustainable and eco-friendly materials.

This study fabricates epoxy/flax composites with TiO₂ particles (0–8 wt%) using hand layup. Composites were tested for wear following American Society for Testing and Materials (ASTM) G99-05. Statistical analysis used Taguchi design of experiments (DOE), with ANOVA identifying key factors affecting SWR in abrasive sliding conditions.

The study illuminates how integrating TiO2 filler particles into epoxy/flax composites enhances abrasive wear properties. Statistical analysis of SWR highlights abrasive grit size (grit) as the most influential factor, followed by normal load, wt% of TiO₂ and sliding distance. Grit size has the highest effect at 43.78%, and wt% TiO₂ filler contributes 15.61% to SWR according to ANOVA. Notably, the Taguchi predictive model closely aligns with experimental results, validating its reliability.

This paper integrates TiO₂ filler and flax fibers to form a novel hybrid composite with enhanced tribological properties in epoxy composites. The use of Taguchi DOE and ANOVA offers valuable insights for optimizing control variables, particularly in natural fiber-reinforced composites (NFRCs).

The purpose of this study is to show which filler metal is the best for hard facing. Because the quality of the surface layer has a great influence on the working life of parts, the purpose was to extend the working life of parts exposed to intensive wear. The tested hard-faced models were made of low carbon steel to save the expensive base metal and to analyze the possibilities of extending the service life of existing structural parts.

Samples were prepared from plates hard faced with various filler metals. Samples were then subjected to experimental testing – testing of tribological properties and hardness and microstructure. Testing was done in conditions similar to real ones – with a sliding speed of 0.25, 0.5 and 1 m/s and with a load of 50, 75 and 100 N and in most rigorous dry conditions. Research was done by using a combination of experimental and theoretical approaches.

The paper shows the results of the experimental testing of four different filler metals aimed for hard facing of parts exposed to highly intensive wear. Results shown that CrWC 600 alloy is the most favorable filler metal for hard facing of parts such as those of construction mechanization and those subjected to intensive abrasive wear at stone mines.

All obtained results are real and fully applicable, as there is a huge industrial need for these types of technologies. With the application of these technologies, beside money savings, the working life of parts can be significantly extended.

The research presented in this paper was conducted because of the lack of results from this area in Serbia and because of the necessity for application of obtained results in companies for road maintenance and stone excavation in the region of Šumadija, Serbia.

The purpose of this paper is to analyse the phenomenon of wear resistance of some metals and alloys with allowance for the stiffness of their stressed‐strained state of the surface.

An original criterion (in the form of limiting deformation power density) of wear resistance on the basis of structure‐energy theory of friction is proposed. Experimental data on the wear resistance are generalized using the criterion for the conditions of hydroabrasive, impact‐abrasive and cavitational erosion.

The dependence of the criterion on stiffness coefficient of the stressed‐strained state of the surface of materials is demonstrated. It has been found that an increase of the stiffness results in the reduction in the energy capacity and wear resistance of both metals and alloys investigated.

The structure‐energy criterion can be used for choosing suitable frictional materials and to compare and estimate the theoretical considerations with experimental data.

The proposed structure‐energy approach allows systemizing the results of our analyses and the experimental data.

This study aims to determine the braking performance of limestone as a filler in brake friction materials.

Samples containing limestone material (30-35-40%), which can be an alternative to brake friction material filler, were produced. The samples were weighed on precision scales, mixed homogeneously and produced using the hot molding method. The physical and tribological properties of the produced samples were determined, and their microscopic analyzes were made with scanning electron microscopy.

As the amount of limestone increased, the density of the samples decreased. The friction coefficient and wear rates were close to each other and within the optimum limits for all samples. Limestone materials can be used instead of barite materials studied in the literature on brake linings. Microcracks were observed only in samples containing 30% and 35% limestone in microscopic images.

In this study, the wear rate, coefficient of friction and microstructures on the friction surfaces of brake friction materials containing limestone were investigated. The usability of limestone as a filler in brake friction materials provides valuable information to researchers and industrial organizations in the brake friction material field.

Oblique impacts which occur in many situations in mineral industries leads to material removal and fail of mechanical parts. Studies will be helpful in optimal design to have minimum machine malfunctions.

In the present work, the Hertz-Di Maio Di Renzo nonlinear model of contact is used to simulate the impact phenomenon as a micro-sliding process. The modified Archard equation is used to evaluate wear over the impact. The wear coefficient is evaluated by a pin-disk machine. An impact-wear tester is used to validate the model results.

The measurements indicate an increase in surface hardness because of the several impacts. It is considered in the wear predictive model.

The model predictions compared with the experimental data, obtained from the impact-wear tester, show that the model well predicts the impact wear and can be used as a predictive tool to study the practical design problems and to explain some phenomena associated with the percussive impact.

Impact of mechanical elements may have the devastating effects including the material breakdown, abnormal deformation, stiffness lowering and the surface wear. In the present study it is showed that covering the impacted targets by the fluid layer will accommodate these effects by absorbing a portion of the impact energy.

In the present work, a drop test machine is used to experimentally investigate the effect of influencing parameters on the impact subsequences. Effect of the impact velocity, incidence angle, ball size, target bed and covering oil/water layer is considered.

Testing the variety of the oil layers thickness revealed that the large portion of the impact energy can be damped by thickening the covering fluid. The ratio of the energy absorbed by the same thickness oil and water layer is extracted. Results show that the energy absorbed by the water layer is lower than half of the energy absorbed by the oil layer in several cases. Moreover, theoretical relations are extracted from the experimental data which give the energy absorption by rubber bed contrast to the steel bed and also the energy absorption by fluid layer contrast to the dry impact.

This paper includes investigating the effect of specimen bed and covering fluid layer on energy absorption by a new experimental apparatus. Layers of oil and water have been compared.

Remanufacturing of worn blades with various defects normally requires processes such as scanning, regenerating a geometrical reference model, additive manufacturing (AM) through laser cladding, adaptive machining and polishing and quality inspection. Unlike the manufacturing process of a new part, the most difficult problem for remanufacturing such a complex surface part is that the reference model adaptive to the worn part is no longer available or useful. The worn parts may suffer from geometrical deformation, distortion and other defects because of the effects of harsh operating conditions, thereby making their original computer aided design (CAD) models inadequate for the repair process. This paper aims to regenerate the geometric models for the worn parts, which is a key issue for implementing AM to build up the parts and adaptive machining to reform the parts. Unlike straight blades with similar cross sections, the tip geometry of the worn tip of a twist blade needs to be regenerated by a different method.

This paper proposes a surface extension algorithm for the reconstruction of a twist blade tip through the extremum parameterization of a B-spline basis function. Based on the cross sections of the scanned worn blade model, the given control points and knot vectors are firstly reconstructed into a B-spline curve D. After the extremum of each control point is calculated by extremum parameterization of a B-spline basis function, the unknown control points are calculated by substituting the extremum into the curve D. Once all control points are determined, the B-spline surface of the worn blade tip can be regenerated. Finally, the extension algorithm is implemented and validated with several examples.

The proposed algorithm was implemented and verified through the exampled blades. Through the extension algorithm, the tip geometry of the worn tip of a twist blade can be regenerated. This method solved a key problem for the repair of a twist blade tip. It provides an appropriate reference model for repairing worn blade tips through AM to build up the blade tip and adaptive machining/polishing processes to reform the blade geometry.

The extension errors for different repair models are compared and analyzed. The authors found that there are several factors affecting the accuracy of the regenerated model. When the cross-section interval and the extension length are set properly, the restoration accuracy for the blade tip can be improved, which is acceptable for the repairing.

The lack of a reference geometric model for worn blades is a significant problem when implementing blade repair through AM and adaptive machining processes. Because the geometric reference model is unavailable for the repair process, reconstruction of the geometry of a worn blade tip is the first crucial step. The authors proposed a surface extension algorithm for the reconstruction of a twist blade tip. Through the implementation of the proposed algorithm, the blade tip model can be regenerated.

Remanufacturing of worn blades with various defects is highly demeaned for the aerospace enterprises considering sustainable development. Unlike straight blades, repair of twist blades encountered a very difficult problem because the geometric reference model is unavailable for the repair processes. This paper proposed a different method to generate the reference model for the repair of a twist blade tip. With this model, repair of twist blades can be implemented through AM to build up the blade tip and adaptive machining to subtract the extra material.

The authors proposed a surface extension algorithm to reconstruct the geometric model for repair of twist blades.

The purpose of this paper is twofold: an approach is proposed to determine the optimum replacement time for shovel teeth; and a risk-quantification approached is developed to derive a confidence interval for replacement time.

The risk-quantification approach is based on a combination of Monte Carlo simulation and Markov chain. Monte Carlo simulation whereby the wear of shovel teeth is probabilistically monitored over time is used.

Results show that a proper replacement strategy has potential to increase operation efficiency and the uncertainties associated with this strategy can be managed.

The failure time distribution of a tooth is assumed to remain “identically distributed and independent.” Planned tooth replacements are always done when the shovel is not in operation (e.g. between a shift change).

The proposed approach can be effectively used to determine a replacement strategy, along with the level of confidence level, for preventive maintenance planning.

The originality of the paper rests on developing a novel approach to monitor wear on mining shovels probabilistically. Uncertainty associated with production targets is quantified.