Cold spray (CS) parameter optimization is necessary to minimize corrosion and enhance the protective properties of composite coatings on lightweight alloys. In the present work, an evolutionary genetic algorithm (GA) was used to identify the optimum combination of CS parameters and further guarantee good corrosion rate minimization and sufficient coating reliability. Yttria-stabilized zirconia (YSZ)-reinforced AA2024 aluminum alloy was cold-sprayed onto AZ31 magnesium alloy substrates. A three-factor, five-level central composite design (CCD) with response surface methodology (RSM) was used to develop a quadratic regression model between corrosion rate and working gas temperature (WGT), nozzle spray distance (NSD), and feedstock flow rate (FFR). Analysis of variance (ANOVA) validated the high statistical significance of the model (F = 193.50, p < 0.0001), high determination coefficients (R2 = 0.9792, adjusted R2 = 0.9643, predicted R2 = 0.9596), and a low coefficient of variation (7.55

Soft computing methods are now powerful aids for optimizing the parameters of material processing and improving wear resistance. This research proposes a hybrid heuristic method for optimizing Friction Stir Processing (FSP) parameters for improved wear properties. This research started by examining the key processing parameters of tool rotation speed, traverse speed, and number of passes using a face-centered central composite design (FCCCD) under response surface methodology (RSM).To determine and optimally wear resistance, an integrated computational approach using RSM, Genetic Algorithm (GA), Artificial Neural Networks (ANN), and Adaptive Neuro-Fuzzy Inference System (ANFIS) was used. The GA-ANN model obtained an accuracy of 95.48%, while the GA-ANFIS model yielded an accuracy of 92.9%, confirming that the two models proved to be appropriate predictive models of wear behavior. Microstructural analysis using Field Emission Scanning Electron Microscopy (FESEM) showed that when using the optimized conditions for FSP, the reinforcement particles dispersed uniformly, reduced the formation of wear debris, and improved wear resistance and tribological properties. The morphology of the worn surfaces demonstrated a change from severe delamination and deep plowing for the lower performing surface to a refined abrasive to explain the reduction in material loss and improved performance. Furthermore, three-dimensional response surface plots illustrated the significant role of rotational speed and the number of passes on wear resistance, underlining the importance of parameter selection for superior tribological performance.

PurposeThis study aims to develop and assess the tribological performance of AA2024-based hybrid composites reinforced with waste industrial stainless steel (SS) grinding particles and eggshell (ES) particles. By using waste materials, the research promotes a circular economy approach for sustainable and lightweight structural applications.Design/methodology/approachHybrid composites were fabricated using the hot press sintering method. Microstructural analysis was conducted to examine reinforcement distribution and porosity. The relative density was measured to assess densification. Microhardness tests were performed to evaluate strengthening mechanisms, while wear analysis was carried out to determine wear rate and the coefficient of friction (COF).FindingsMicrostructural analysis confirmed a homogeneous distribution of reinforcements with minimal porosity (approximately 5.12% in AA2024 + 3ES + 4SS). The composites exhibited relative densities between 92% and 94.5%, demonstrating effective densification. Microhardness increased from 92.4 +/- 3.1 HV (AA2024) to 128.6 +/- 4.2 HV (AA2024 + 3ES + 4SS), attributed to grain refinement and reinforcement hardening effects. The lowest wear volume loss (3.293 mm3) and the COF (0.38) in AA2024 + 3ES + 4SS, indicating enhanced tribological performance.Originality/valueThis study introduces a novel approach to developing hybrid aluminum composites using industrial and biowaste reinforcements, offering a sustainable and cost-effective alternative for aerospace and automotive applications.

The main purpose of the present investigation is to optimize the friction stir processing parameters in the fabrication of the YSZ/Al2O3 particulate-reinforced AZ31 magnesium alloy-based surface composites with enhanced porosity and corrosion rate. In the present work, the response surface method based on the central composite design was used to study the effects of the tool rotational speed, tool traverse speed, and tool axial force on the porosity and corrosion rate of the AZ31 magnesium alloy-based surface composites. In the present work, the developed response surfaces based on the prediction of the porosity and corrosion rate of the AZ31 magnesium alloy-based surface composites were statistically significant, with a high predictive accuracy of R2 = 0.9928 and R2 = 0.9954, respectively. Sensitivity analysis showed that the tool traverse speed had the highest effect on the AZ31 magnesium alloy-based surface composites, followed by the tool rotational speed and the tool axial force. Using the multi-response optimization method based on the Aquila Optimizer Algorithm, the optimum friction stir processing parameters in the fabrication of the AZ31 magnesium alloy-based surface composites were determined as a tool rotational speed of 1136.234 rpm, a tool traverse speed of 104.426 mm/min, and a tool axial force of 10.621 kN. At the optimum friction stir processing parameters, the surface composite revealed an optimum porosity of 1.12

Magnesium alloys are increasingly considered for lightweight structural applications in the automotive and aerospace sectors; however, their poor surface durability and limited wear resistance under sliding conditions restrict broader tribological use. In this study, coatings based on the AA2024 and reinforced with yttria-stabilized zirconia were applied to AZ31B magnesium alloy substrates using a low-pressure cold spray process to increase their surface hardness, interfacial adhesion, and tribological behavior. Coatings were produced with yttria-stabilized zirconia content of 5, 10, and 15 wt.% and then tested systematically. Microstructural and elemental analyses confirmed dense coatings with uniform ceramic dispersion and a mechanically interlocked coating-substrate interface. The hardness increased with increasing reinforcement content and reached a maximum value of 216 HV for the coating containing 15 wt.% yttria-stabilized zirconia (YSZ), while the porosity remained as low as 1.5%. Among the investigated compositions, the coating containing 10 wt.% YSZ exhibited the highest adhesion strength of 58.32 MPa, representing improvements of approximately 49.7% and 30.0% compared with the coatings containing 5 and 15 wt.% reinforcement, respectively. This composition also demonstrated superior tribological performance, achieving the lowest specific wear rate of 1.5 & times; 10-4 mm & sup3;/N & centerdot;m, corresponding to a 78.6% reduction relative to the uncoated substrate. Surface roughness measurements and wear-track morphology further confirmed the enhanced wear stability through lower roughness values (Ra = 2.335 & micro;m, Rq = 2.836 & micro;m) and more uniform wear tracks. Thus, the current results indicate that the 10 wt% of YSZ with AA2024, making them promising for durable lightweight components subjected to sliding contact.

Magnesium (Mg) alloys, particularly AZ31, are increasingly utilized in the automotive and aviation industries due to their lightweight nature and high strength-to-weight ratio. However, their limited corrosion resistance poses challenges for broader applications. This study addresses this limitation by applying AA2024/Al 2 O 3 cermet coatings on AZ31 Mg alloy using the cold spray (CS) technique. Empirical correlations were developed to predict the corrosion rate and porosity of the coated deposits using response surface methodology (RSM). Analysis of variance (ANOVA) results confirmed the statistical significance of the developed models, with R 2 values of 0.9973 for porosity and 0.9971 for corrosion rate, demonstrating strong predictive accuracy. The effects of key CS process parameters—processing temperature (PT), spray distance of the gun (SDG), and powder feed rate (PFR) —were systematically evaluated. The optimal parameters were determined to be a PT of 530℃, an SDG of 13 mm, and a PFR of 23 g/min, achieving a corrosion rate of 1.29 mm/year (actual) and 1.45 mm/year (predicted), with porosity values of 1 vol.% (actual) and 0.99 vol.% (predicted). Coating characterization revealed enhanced corrosion resistance due to improved deposit density and minimized defects. This work provides a robust framework for optimizing CS process parameters to extend the applicability of Mg alloys in corrosive environments.

Growing environmental concerns have intensified the search for cleaner fuels and eco-friendly combustion strategies for internal combustion engines. This study investigates the effects of ethanol and methanol fumigation on the performance, combustion, and emission characteristics on a multi-cylinder DI diesel engine operating on blends of waste plastic oil (WPO). Tests were conducted with fumigation rates varying from 20 to 100 g/h to quantify brake thermal efficiency (BTE), in-cylinder pressure, total heat release rate (THRR), and NOx/smoke emissions. The maximum performance was achieved at a fumigation rate of 60 g/h at which BTE increased from 26.5% with WPO to 29.8% with methanol and 28.9% ethanol, respectively. The maximum cylinder pressure increased from 72.5 to 76.2 bar with methanol and to 74.8 bar with ethanol, relative to the D80WPO20 baseline. The maximum THRR increased from 70 J/degrees CA at baseline to 91 J/degrees CA with methanol and to 89 J/degrees CA with ethanol. Methanol fumigation decreased NOx emissions by about 15% compared to WPO alone and smoke opacity improved with methanol and ethanol fumigation, decreasing from 52% with WPO to 44% and 46%, respectively, at 80 g/h. In general, methanol showed higher performance because it has a higher oxygen content and vaporizes faster, leading to more complete combustion. Therefore, alcohol fumigation of WPO-fueled engines is a viable path to improved performance and emission reductions, contributing to more sustainable energy use and environmental protection.

The primary obstacle in cold spraying (CS) is choosing the optimum set of spray parameters to implement in order to attain the desired coating properties. To find the optimum set of spray parameters for CSed AA2024/Al2O3 cermet coating on AZ31Mg alloy, the response surface methodology (RSM) and particle swarm optimization (PSO) techniques were utilized. In order to create an interaction among the process variables temperature (TEMP), nozzle spray distance (NSD), and powder delivery rate (PDR) and with the deposit properties (wear loss), So in this study, an experimental test was planned, conducted, executed, and empirical relationships were developed by creating a three-factor, five-level central composite rotatable design matrix (CCRDM) through RSM approaches to predict the wear loss of CSed cermet coatings. The established empirical relationship was optimized through PSO. The RSM was compared with the optimized value found by PSO. As a result, the optimized parameters of TEMP of 550 degrees C, the NSD of 15 mm, and a PDR of 25 gpm resulted in a minimum wear loss of 2.52 mg through the RSM. On the other hand, the optimized value obtained using particle swarm optimization for the response wear loss is 2.421 mg with a TEMP of 550.634 degrees C, an NSD of 15.534 mm, and a PDR of 25.645 gpm. When CS coating parameters are optimized using RSM and PSO, PSO produces more precise results than RSM. From the ANOVA findings, TEMP was determined to be the most influential parameter, followed by NSD and PDR.

The mechanical, microstructure, wear and electrochemical corrosion properties of Ti6Al4V/xTiB2-xTiC (x = 0, 2.5, 5, and 7.5 vol.%) hybrid composites, produced by powder metallurgy, were studied in relation to their reinforcement percentage. Initially, mechanical investigations were carried out to assess the mechanical attributes of the composites. Additionally, the wear and friction behavior of the composites was examined using a pin-on-disk apparatus under various conditions. The Scanning electron microscope and X-ray diffraction analysis were carried out to understand the microstructural changes and elemental compositions of the specimens. Electro Chemical Corrosion experiments were conducted under simulated body environments, such as 37 degrees C and simulated body fluid. The findings revealed that the homogeneous distribution of reinforcements into the titanium (Ti) matrix, led to significant microstructural changes, achieving maximum hardening of the Ti6Al4V with 5 vol.%TiB2-TiC. In comparison to the Ti6Al4V alloy, the Ti6Al4V/5%TiB2 & 5% TiC composite exhibits a 48% increase in hardness and a 18% decrease in porosity. According to the corrosion test findings, the Ti6Al4V/5% TiB2 & 5%TiC hybrid composites exhibited superior corrosion behaviour than the alloy, with a corrosion current density of 1.0 x 10-6 A/cm2. These results provided valuable insights into the relationship between composition, microstructure, and the enhanced corrosion potentials of the alloy and composites.

The degradation of engineering materials owing to erosion-corrosion remains a critical challenge in industries such as marine, oil and gas, mining, and slurry transportation, where components are exposed to aggressive environments. This study investigates the effectiveness of High-Velocity Oxyfuel (HVOF)-sprayed WC-10Ni-5Cr coatings in enhancing the erosion-corrosion resistance of 35CrMo steel, a widely used structural material in such demanding applications. The erosion-corrosion behaviour of WC-10Ni-5Cr coatings was systematically analysed in a 3.5 wt-% NaCl solution containing silica sand as the erodent under varying operational parameters, including sand concentration, rotational speed, and exposure time. Microstructural characterisation, volume loss measurements, and surface morphology analyses were conducted to elucidate degradation mechanisms. Results reveal that uncoated 35CrMo steel exhibits a severe volume loss of 3.21 mm(3), whereas the coated counterpart demonstrates a significantly lower volume loss of 0.056 mm(3), corresponding to a 76% reduction in material loss. Also, corrosion rate analysis indicates that the uncoated steel corrodes at 0.417 mils per year (mpy), whereas the WC-10Ni-5Cr coating reduces the corrosion rate to 0.108 mpy, representing a 74.1% improvement in corrosion resistance. This study conclusively establishes that HVOF-sprayed WC-10Ni-5Cr coatings offer exceptional protection against erosion-corrosion, significantly extending the service life of 35CrMo steel in aggressive environments. La d & eacute;gradation des mat & eacute;riaux d'ing & eacute;nierie en raison de l'& eacute;rosion-corrosion demeure un d & eacute;fi critique dans les industries telles que la marine, le p & eacute;trole et le gaz, l'exploitation mini & egrave;re et le transport de suspension, o & ugrave; les composants sont expos & eacute;s & agrave; des environnements agressifs. Cette & eacute;tude examine l'efficacit & eacute; des rev & ecirc;tements de WC-10Ni-5Cr projet & eacute;s par oxy-carburant & agrave; haute v & eacute;locit & eacute; (HVOF) pour am & eacute;liorer la r & eacute;sistance & agrave; l'& eacute;rosion-corrosion de l'acier 35CrMo, un mat & eacute;riau de structure largement utilis & eacute; dans des applications aussi exigeantes. On a analys & eacute; syst & eacute;matiquement le comportement & agrave; l'& eacute;rosion-corrosion des rev & ecirc;tements de WC-10Ni-5Cr dans une solution de 3.5% en poids de NaCl contenant du sable siliceux comme & eacute;rodant, sous divers param & egrave;tres op & eacute;rationnels, notamment la concentration en sable, la vitesse de rotation et le temps d'exposition. On a effectu & eacute; une caract & eacute;risation microstructurale, des mesures de perte volumique et des analyses de morphologie de surface afin d'& eacute;lucider les m & eacute;canismes de d & eacute;gradation. Les r & eacute;sultats r & eacute;v & egrave;lent que l'acier 35CrMo non rev & ecirc;tu pr & eacute;sente une perte de volume s & eacute;v & egrave;re de 3.21 mm3, tandis que son homologue rev & ecirc;tu d & eacute;montre une perte volumique significativement moindre de 0.056 mm3, correspondant & agrave; une r & eacute;duction de 76% de la perte de mati & egrave;re. & Eacute;galement, l'analyse du taux de corrosion indique que l'acier non rev & ecirc;tu se corrode & agrave; 0.417 mils par an (mpy), tandis que le rev & ecirc;tement de WC-10Ni-5Cr r & eacute;duit le taux de corrosion & agrave; 0.108 mpy, repr & eacute;sentant une am & eacute;lioration de 74.1% dans la r & eacute;sistance & agrave; la corrosion. Cette & eacute;tude & eacute;tablit de mani & egrave;re concluante que les rev & ecirc;tements de WC-10Ni-5Cr projet & eacute;s par HVOF offrent une protection exceptionnelle contre l'& eacute;rosion-corrosion, prolongeant de mani & egrave;re significative la dur & eacute;e de vie de l'acier 35CrMo dans les environnements agressifs.

Global warming and natural calamities have driven scientists and researchers to explore renewable and eco-friendly raw materials for industrial and other applications. Traditionally, structural components in various fields are made of plastic, which is harmful to the environment, or heavy metallic materials, which consume excessive energy during dynamic operations, leading to increased fossil fuel consumption. Composite materials have emerged as a promising substitute for these environmentally detrimental materials. Among them, plant-based fiber-reinforced polymer composites, derived from renewable and abundant natural fibers, have gained significant attention due to their environmental benefits, cost-effectiveness, and potential for sustainability. Recent trends in this field include the development of hybrid composites, the incorporation of advanced biopolymers, and improved processing techniques to enhance mechanical and thermal performance. However, challenges such as interfacial bonding, water absorption, and durability under extreme conditions still hinder their broader adoption. This review explores the advancements in plant-based fiber-reinforced polymer composites, emphasizing recent progress, ongoing challenges, and future potential. It aims to provide comprehensive insights for researchers and practitioners focusing on this rapidly evolving domain.

Alumina-reinforced AA2024 metal matrix composite (MMC) coatings were deposited on AZ31 magnesium alloy substrates by the cold spray (CS) method, with different alumina volume fractions of 20, 35, 50, and 65 vol.%. This study investigates the influence of alumina reinforcement on the microhardness, internal cohesion, and tribological performance of the MMC coatings. Experimental observations indicate that elevated alumina content increases the plastic deformation of AA2024 particles and improves the microhardness of the coatings. The addition of alumina increases the internal cohesive strength of the MMC coating; however, at high reinforcement levels, this strength degrades primarily due to reduced effective contact between metallic particles caused by excessive ceramic material. Therefore, the tribological research verifies that both the presence and increasing concentration of alumina particles have a strong impact on the wear behaviour of the AA2024/alumina MMC coatings deposited on AZ31 substrates. On a d & eacute;pos & eacute; des rev & ecirc;tements composites & agrave; matrice m & eacute;tallique (MMC) AA2024 renforc & eacute;s d'alumine sur des substrats en alliage de magn & eacute;sium AZ31 par projection & agrave; froid (CS), avec diff & eacute;rentes fractions volumiques d'alumine de 20, 35, 50 et 65% en vol. Cette & eacute;tude examine l'influence du renfort d'alumine sur la microduret & eacute;, la coh & eacute;sion interne et les performances tribologiques des rev & ecirc;tements MMC. Les observations exp & eacute;rimentales indiquent qu'une teneur & eacute;lev & eacute;e en alumine augmente la d & eacute;formation plastique des particules d'AA2024 et am & eacute;liore la microduret & eacute; des rev & ecirc;tements. L'ajout d'alumine augmente la force de coh & eacute;sion interne du rev & ecirc;tement MMC; cependant, aux niveaux & eacute;lev & eacute;s de renfort, cette force se d & eacute;grade en raison principalement d'une r & eacute;duction du contact effectif entre les particules m & eacute;talliques due & agrave; un exc & egrave;s de mat & eacute;riau c & eacute;ramique. Donc, les recherches tribologiques confirment que la pr & eacute;sence et la concentration accrue de particules d'alumine ont un impact important sur le comportement & agrave; l'usure des rev & ecirc;tements MMC AA2024/alumine d & eacute;pos & eacute;s sur des substrats en AZ31.

The optimization of friction stir process (FSP) parameters plays a pivotal role in enhancing the mechanical properties of friction‐stirred hybrid surface composites (FSHSC), which are crucial for lightweight and high‐performance structural applications. This study introduces the use of the artificial bee colony algorithm (ABCA) for optimizing process parameters of yttria‐stabilized zirconia (YSZ) and alumina (Al2O3)‐reinforced FSHSC. A three‐factor, five‐level central composite design matrix based on response surface methodology is utilized to develop predictive models for ultimate tensile strength (UTS) and yield strength (YS). Analysis of variance confirms the robustness and reliability of the models, with high statistical significance (p < 0.0001) and R2 values of 0.9940 for UTS and 0.9938 for YS. ABCA identifies optimal parameters—tool rotational speed of 1001.543 rpm, tool transverse speed of 71.896 mm min−1, and tool axial force of 7.23 kN—achieving UTS of 198.345 MPa and YS of 163.534 MPa. The study demonstrates that ABCA is a powerful tool for optimizing FSP parameters and improving hybrid composite performance. This methodology offers a framework for advancing the mechanical properties of composites, with significant implications for lightweight engineering applications.

This research investigates the impact of various tool pin profiles on the tribological behavior of AZ31 magnesium alloy reinforced with 5 wt.% yttria-stabilized zirconia (YSZ) surface composite produced through friction stir processing (FSP). AZ31 plate filled with YSZ subjected to FSP using four distinguished tool profiles: plain cylindrical (PC), threaded cylindrical (TC), plain tapered cylindrical (PTC) and threaded tapered cylindrical (TTC). Dynamic recrystallization due to the FSP process contributed to fine grain structure refinement and uniform distribution of YSZ particles, resulting in improved hardness of AZ31/YSZ surface composites. The wear behavior was examined by means of a pin-on-disc tribometer under 15, 30, and 45 N applied loads. Results reveal that the FSPed AZ31/YSZ composites had higher wear resistance compared with those for as-received, and FSPed AZ31 alloy. Plain tapered cylindrical tool profile gave better outcomes which included defect free surface finish and optimal particle dispersion. It was shown that stronger YSZ particles inhibit material removal and increased refined grain structure, supported by a decrease in coefficient of friction from 0.49 for as received AZ31 alloy to 0.27 for FSPed AZ31/YSZ composites emphasizes the influence of FSP tool pin profiles in enhancing the hardness and tribological performance of surface composites.

Lanthanum zirconate (LZ) is a promising material for thermal barrier coatings (TBCs) due to its low thermal conductivity, high phase stability, reflectivity, and lower annealing activity compared to yttria-stabilized zirconia (YSZ). However, LZ's insulating performance deteriorates at elevated temperatures due to increased radiative heat transfer. In this study, plasma-sprayed LZ and YSZ in equal weight proportions (50:50) onto Inconel 718 substrates. Reflectivity was measured using UV–VIS spectrometers, and porosity was determined through optical microscopy with image analysis. Empirical models were developed to correlate atmospheric plasma spraying (APS) parameters (power, spray distance, and powder feed rate) with porosity and reflectivity using central composite design (CCD) and response surface methodology (RSM), validated by ANOVA. The models achieved R2 values of 0.9972 for porosity and 0.9903 for reflectivity, indicating strong agreement with experimental data. Power was the most influential parameter, followed by spray distance and feed rate. Annealing at 1200 °C for 4 h resulted in a maximum reflectance of 89

Friction stir processing (FSP) parameter optimization is critical in the reduction of wear loss and improvement of the tribological performance of hybrid surface composites (HSCs). In this study, the optimization by the genetic algorithm (GA) of FSP parameters for YSZ and Al2O3-reinforced AZ31 magnesium alloy surface composites was done along with response surface methodology (RSM). A central composite design (CCD) consisting of three factors-tool traverse speed (TTS), tool rotational speed (TRS), and tool axial force (TAF)-all at five levels, was used to develop an empirical relationship for the prediction of wear loss. Analysis of variance (ANOVA) verified the statistical significance of the models with R2 = 0.9932, confirming high predictive ability. Sensitivity analysis indicated that TRSexerted the strongest control over wear loss, followed by TTS and TAF. The desirability analysis provided a combined desirability value of 0.8675, which showed effective optimization for further improvement. TRS, TTS, and TAF all achieved individual desirability values of 1, which validated their optimal choice. The GA optimization found the optimal FSP parameters-TRSof 1324.736 rpm, a TTS of 123.676 mm/min, and a TAF of 12.336 kN with wear loss of 2.953 mg. Microstructural analysis identified even dispersion of the reinforcements and the improved grain structure, lending better wear resistance. The result highlights the effectiveness of GA to optimize FSP parameters and present a strategic path toward the wear improvement of HSCs in aviation and automotive sectors.