Introduction. Roller burnishing is one of the most popular methods for improving the surface quality of a workpiece, increasing its wear resistance, microhardness and corrosion resistance. During the processing, the workpiece is compressed and smoothed under the pressure of hardened roller. Purpose of the work. The results of the research show that the introduction of minimum quantity lubrication (MQL) during roller burnishing makes it possible to increase the efficiency of the process by reducing friction and improving lubrication. Studies have shown that the use of nanofluids under MQL conditions improves the machining performance. However, very little attention has been paid to the roll burnishing of Al6061-T6 alloy under nano minimum quantity lubrication (NFMQL) conditions. The methods of investigation. In light of this, this study compares the performance of roll burnishing of Al6061-T6 alloy under dry friction conditions and NFMQL conditions. The microhardness, roundness, and surface roughness are evaluated, modeled, and optimized in the study by considering the cutting speed, feed rate, and number of passes. Based on the experimental results, mathematical models are established to predict the surface roughness, microhardness, and roundness deviation. Results and Discussion. The developed models of surface roughness, microhardness and roundness deviation show the R-square value higher than 0.9, which allows these models to be confidently used to predict the studied responses under dry friction conditions and under NFMQL conditions within the parameter domain selected in this work. According to this study, the machining performed in four passes at a cutting speed of 357 rpm and a tool feed of 0.17 mm/rev can obtain the lowest roundness deviation (3.514 μm), the best microhardness (130.19 HV) and the lowest surface roughness (0.64 μm). Further, the study shows that increasing the number of passes (more than four) does not lead to a significant improvement in surface roughness or microhardness. However, it leads to a slight increase in roundness deviation. Therefore, it is recommended to use a maximum of four passes during roll burnishing of Al6061-T6 aluminum alloy specimens under dry friction conditions to achieve optimal results. The obtained results imply that roller burnishing can effectively improve the overall surface quality and hardness of the workpiece. In addition, roller burnishing is regarded as an affordable method to enhance the functionality and strength of the machined parts by reducing the occurrence of surface defects such as scratches and cracks. It is found that the surface roughness decreases with the increase of the cutting speed. However, it is observed to increase under both dry friction and NFMQL conditions when the cutting speed is increased to 360–380 rpm. Moreover, it is found to decrease with the increase of the feed and the number of passes. But after three or four passes at a feed rate of 0.2–0.25 mm/rev, a noticeable increase in the surface roughness is observed. It is noticed that with the increase of the feed, the microhardness and the roundness deviation increase. In addition, as the number of passes increases, the roundness deviation decreases and the microhardness increases. The number of passes under dry friction condition and feed rate under NFMQL rolling has significant effects on the surface roughness. The cutting speed seems to have the greatest effect on the microhardness, followed by feed rate and the number of passes. On the other hand, the effect of increasing microhardness under NFMQL conditions seems to be stronger. Under dry friction condition, the cutting speed has a significant effect on the roundness deviation, and under NFMQL conditions, the feed rate has an effect.

Introduction. Roller burnishing is one of the most common methods of improving the surface quality of parts, wear resistance, microhardness, and corrosion resistance. The process involves compressing and smoothing the workpiece using the pressure of a hardened roller. It is often used to improve part performance and lifespan in sectors including automotive, aerospace, and medical equipment manufacturing. The literature reviewed shows that the roller burnishing process effectively improves the overall surface quality and hardness of the workpiece. In addition, roller burnishing is considered as an affordable method to enhance the functionality and robustness of machined parts by reducing the likelihood of surface defects such as like scratches and cracks. However, very few studies have been reported on the modeling and optimization of roller burnishing of Al6061-T6 for minimum surface roughness, better microhardness, and roundness. The methods of investigation. In the current work, roller burnishing of Al6061-T6 is modeled and optimized for superior microhardness, roundness, and minimal surface roughness. Under dry-cutting conditions, the performance of roller burnishing of Al6061 specimens is assessed in terms of process factors such as cutting speed, feed, and number of passes. Mathematical models to predict the surface roughness, microhardness, and deviation in roundness are developed based on the experimental results. Results and Discussion. The coefficient of correlation for the developed models is found to be close to 0.9, which indicates that it can be reliably used to predict and optimize the roller burnishing of the Al6061-T6. According to this study, the use of the following cutting parameters leads to the lowest variation in roundness (4.282 µm), the better microhardness (119.2 Hv), and the lowest surface roughness (0.802 µm): cutting speed 344 rpm, feed 0.25 mm/rpm and four passes. Further, the study reveals that increasing the number of passes (beyond four) does not significantly improve the surface roughness or microhardness. However, it does lead to a slight increase in the roundness deviation. Therefore, in order to achieve optimal results, it is recommended to use a maximum of four passes during roller burnishing of Al6061 specimens under dry cutting conditions. These results imply that roller burnishing can effectively improve the overall quality and hardness of the workpiece surface. In addition, roller burnishing is considered as an affordable method to increase the functionality and robustness of machined parts by reducing the likelihood of surface defects like scratches and cracks.

Aluminum, one of the most abundant metals found on our planet, plays a crucial role in manufacturing as it is lightweight and resistant to corrosion and has excellent machinability. Of its numerous alloys, Al6061 is one of the most popular alloys used for CNC machining due to its superior mechanical and processing properties. This paper aims to investigate the impact of machining under dry and wet machining conditions. Correspondingly, the impact of dry machining on the material removal rate (MRR) and surface roughness (Ra) of Al6061 was evaluated. Machining was performed on a CNC Lathe. Two rods of Al6061 were used, and a dynamometer was attached to them to measure the radial, thrust, and tangential forces. In wet machining, the coolant used was a mixture of cutting oil and water. Different RPMs, feed rates, and depths of cut were entered into the machine as parameters. And the optimum parameters where found. This research utilizes particle swarm optimization approaches in order to evaluate optimal parameters, in contrast to traditional measurement methods such as contact profilometry or cutting force measurement. The results indicate that surface roughness rises with the depth of cut and feed rate. Ra rises by about 200% when dry machining is conducted at 0.05 mm/rev with increased depths of cut from 0.5 mm to 2.5 mm. In wet machining, the rise is much smaller, approximately 67% at 0.05 mm/rev and 30% at 0.25 mm/rev. Wet machining always produces more finished surfaces, decreasing Ra by 22–25% over dry machining. Wet machining is therefore better suited for achieving high-quality surface finish in Al6061 machining.

Introduction. One of the most significant phenomena in every industrial sector is friction and wear, which inevitably occurs when there is relative motion between similar or dissimilar materials. A substantial portion of global energy production is estimated to be expended in overcoming friction and wear, making them critical factors in energy efficiency and sustainability. Recently, advances in materials science, lubrication technologies, and innovative design approaches have facilitated a significant reduction in friction and wear, leading to considerable energy savings and extended component lifespan. Polytetrafluoroethylene (PTFE), among other materials, has revolutionized the tribological field, emerging as a highly effective synthetic polymer. This is attributed to its exceptional properties, including a low coefficient of friction, chemical inertness, thermal stability, non-stick characteristics, and biocompatibility. These unique properties make PTFE an ideal material for various industrial applications, spanning from aerospace to biomedical sectors. The purpose of work. This study aims to conduct a comprehensive numerical and experimental investigation into the tribological properties of PTFE-based composites. The materials selected for investigation include pure PTFE, PTFE with 25% carbon (C) filler, and PTFE with 20% glass filler. Testing was performed using stainless steel (SS 304) as the counterbody. Tribological testing and subsequent evaluation were conducted under dry sliding friction conditions, considering key parameters such as load, sliding speed, and temperature. Response surface methodology (RSM) was employed to develop an empirical model, utilizing experimental data to predict the wear resistance of these materials. Empirical models were developed to understand the influence of process parameters on wear behavior and to optimize operating conditions for minimizing material loss. Method of investigation. Archard's wear model was used as the theoretical framework for predicting volume loss and specific wear rate based on numerical simulations. The wear coefficient (K) was determined through experimental testing and used as an input parameter in the numerical models. Numerical simulations were developed using the finite element analysis (FEA) software ANSYS, enabling the simulation of complex tribological interactions between the composite materials and the counterbody. A central composite rotatable design (CCRD) within the framework of RSM was used to structure the experiments. The experiments were conducted under dry sliding friction conditions using pin on disc tribometer. The input parameters for the experiments were load (ranging from 15 N to 200 N), sliding speed (ranging from 400 rpm to 1000 rpm), and temperature (ranging from 60 °C to 200 °C). Each experiment was conducted for a sliding distance of 5 km to ensure sufficient wear for analysis. A total of 20 experiments were performed for each material, providing a comprehensive dataset for statistical analysis and model validation. Result and discussion. The results of the study highlight the effectiveness of numerical simulation in predicting the wear resistance of PTFE-based composites under dry sliding friction conditions. Experimental investigations reveal that pure PTFE exhibits low mechanical strength, leading to a high wear rate, whereas PTFE with carbon and glass fillers demonstrates improved wear resistance characteristics. The addition of carbon to PTFE enhances the composite's performance by forming a stable transfer film on the counterbody, while the addition of glass promotes increased hardness and, consequently, reduced material loss. Empirical models developed using response surface methodology (RSM) confirm that the applied load on the pin is the most significant parameter affecting wear, followed by sliding speed and temperature. Numerical simulations based on Archard's wear model exhibit good agreement with experimental data, validating the accuracy of the numerical simulations. This research contributes to a deeper understanding of the application of PTFE-based composites in extending the service life and enhancing the reliability of industrial products.

Renewable energy sources coming from solar energy is largely available in nature. The big problem with the sun system is that hardly any amount of sun's energy is utilized by photovoltaic (PV) systems. PV systems are fine only if the panels can be kept perpendicular to the direction of the radiations of the sun. Such a system should, therefore, essentially lead to keeping the PV panel in an optimal position such that at all times it is perpendicular to the sun radiation. This research aims at reviewing several solar tracking methods to attempt to identify the optimal PV panel orientation. The numerous technologies found in the solar tracking system have been studied based on research, such as a passive solar tracker, an active solar tracker, and degrees of movement of the solar tracking system, which includes both single and double axes. Tracking performance, benefits, and drawbacks of the existing solar tracking systems are also provided by this study. Limits of the solar tracking devices are also pinpointed as improvement areas for the near future. In addition, the latest development of a solar tracking system with artificial intelligence and machine learning, which is also focused in this research, is considered. The most successful sun tracking technique discovered during this research is an energetic solar monitor with multiple axis rotation.

The present research investigates the relevance of ISO 14001 certification in ensuring environmental sustainability and minimizing CO₂ emission in different industries, focusing particularly on SAARC nations, such as agriculture, manufacturing, and food processing industries. In using innovative techniques like Grey Relational Analysis (GRA) and Grey-TOPSIS, the research compares data from 2000 to 2014 to analyze the association between ISO 14001 implementation and renewable energy consumption. The results suggest that ISO 14001 certification, when combined with renewable energy schemes, plays an important role in reducing CO₂ emissions—especially in countries like India under severe environmental challenges. Sectoral challenges continue to exist, though, particularly in agriculture and food processing, owing to imprecise definitions of sustainability and laxly enforced regulations. Big companies are more successful in putting into practice ISO 14001 since they attain better environmental and economic performance than small and medium-sized businesses (SMEs), which experience financial and operational limitations. On a worldwide level, Europe is the leader in the uptake of ISO 14001 because of rigorous regulation and demand for sustainability from consumers, while developing markets are behind, calling for specific policy interventions and campaigns. The research highlights ISO 14001's potential for transformation when integrated with renewable energy and policy contexts, and provides useful lessons for policymakers and industry captains seeking to develop sustainable development practices.