Fiber-reinforced additive manufacturing components have been used in various industrial applications in recent years, including in the production of aerospace, automobile, and biomedical components. Compared to conventional methods, additive manufacturing (AM) methods can be used to obtainin lighter parts with superior mechanical properties with lower setup costs and the ability to design more complex parts. Additionally, the fabrication of onyx composites using the conventional method can result in delamination, which is a significant issue during composite machining. To address these shortcomings, the fabrication of onyx composites via additive manufacturing with the Mark forged 3D-composite printer was considered. Machinability tests were conducted using abrasive water jet machining (AWJM) with various drilling diameters, traverse speeds, and abrasive mass flow rates. These parameters were optimized using Taguchi analysis and then validated using the Genetic algorithm (GA) and the Moth Flame Optimization algorithm (MFO). The surface morphology (D_max) and the roughness of the drilled holes were determined using a vision measuring machine with 2D software (MITUTOYO v5.0) and a contact-type surface roughness tester. Confirmation testing demonstrated that the predicted values werenearly identical to the experimental standards. During the drilling of an onyx polymer composite, regression models, genetic algorithms and the Moth-Flame Optimization algorithm were used to estimate the response surface of delamination damage and surface roughness.

Solar thermal collector technology is crucial for capturing renewable energy to support sustainable thermal uses. Nonetheless, traditional designs frequently experience optical losses, ineffective thermal storage and variable performance under different levels of sunlight. This review conducts a systematic assessment of the development and categorization of solar thermal collectors, spanning from non‐concentrating to high‐concentration systems. It emphasizes their thermal efficiency, sustainability, and performance based on application, through an in‐depth comparative analysis of their thermal characteristics, optical efficiency, structural progress, and material advancements. This review is unique in its combination of hybrid nanofluids, PCMs, innovative receiver designs, and passive tracking options to emphasize synergistic enhancements. Recent advances in experimental techniques have shown that high‐efficiency solar concentrators, such as refractive secondary systems, can achieve optical efficiencies surpassing 90%. When these are paired with heat transfer fluids enhanced by nanofluids, thermal efficiency can be boosted by approximately 53%. Moreover, fully replacing fossil fuel heating with optimized solar thermal systems can lead to CO ₂ emission reduction ranging from 69% to 77%. The results emphasize the crucial role of integrating design to enhance performance. This broader implication serves as a guide for creating compact, affordable and highly efficient solar thermal systems designed for both industrial and decentralized uses.

Plant fibers over the years have succeeded in generating interest among researchers about their use. This is mainly due to several ecological legislations put in place by nations to counter the rise in global warming levels. Although plant fiber-based polymer composites are penetrating various domains, concern regarding their suitability and challenges related to manufacturing techniques needs to be addressed. This review attempts to discuss various aspects of plant fibers, their processing with polymer, and methods to improve the fib-matrix interaction. The article also presents an insight into different 3D printing techniques such as fused deposition modeling, laminated object manufacturing, stereolithography, selective laser sintering, and inkjet printer for processing fiber-based polymer composites. The use of technologically advanced 4D printing of fiber-polymer composites is also discussed. Challenges and futuristic opportunities associated with recent works on 3D printing techniques are analyzed toward the end. The paper is structured in the following manner: the first part focuses on natural fibers with their constituents, their processing, and manufacturing techniques with polymers, while the second part of the paper discusses various 3D printing techniques with their challenges and opportunities.

Titanium–silicon oxynitride sulfite (TiSiNOS) is a coating material that is deposited on H13 tool steel using the scalable pulsed power plasma (S3P) technique, where the coating deposition is a hybrid process consisting of a mix of sputtering and arc evaporation. The maximum hardness and coating thickness measured on TiSINOS-coated H13 tool steel are 38 GPa and 3.1 µm, respectively. After implementing the L₉ orthogonal array, nine samples were coated with TiSiNOS, which consists of the same properties. The nine coated and uncoated samples were tested separately based on the L₉ pattern to achieve accurate results. The experimental results indicate that the wear loss can be reduced by minimizing the load at 25 N even if the temperature rises to 250 °C. SEM analysis reveals that the uncoated sample has higher wear loss when compared with the coated samples, and material pullout is visible from the uncoated sample. Based on these results, it can be concluded that TiSINOS coating in H13 tool steel helps in improving the tool life during the drilling process. Taguchi was used in this research to evaluate the wear behavior. The data observed from the experiment were analyzed using the Minitab tool. The most crucial factor is to determine the effects of process parameters. A higher temperature influenced the wear behavior of the tool.