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Plasma electrolytic polishing (PeP) is an anodic surface finishing method that achieves localized dissolution and smoothing of metal surfaces. Unlike conventional fluoride-based electrolytes reported in the literature, the present electrolyte combination incorporates hydrochloric acid (HCl) as an additional constituent to mitigate fluoride retention on the polished surface and modulate electrolyte conductivity during processing. This study systematically investigated the effect of controlled HCl addition (0.1%, 0.3%, and 0.5%) on the polishing efficiency, surface roughness, gloss, and material removal rate (MRR) of TC4 alloy processed by PeP. To assess the long-term stability of the electrolyte combination and its practical viability for repeated industrial application, the effects of electrolyte reusability (first, second, and third use) and polishing time (120, 180, and 240 s) on surface quality were also examined. Owing to the selective dissolution mechanism of PeP, MRR decreased with increasing polishing time. At 240 s, surface roughness improved from 4.5 to 0.558 µm, while gloss increased nearly threefold, from 15.6 to 56.06 GU. Corner diameter increased in regions of initial electrolyte contact, attributed to locally lower electrical resistance and higher current density at the corners. Electrolyte reuse progressively reduced process performance, diminishing roughness and gloss improvements while intensifying corner damage.

Through this article, the manufacturing possibility, mechanical response, and dynamic characteristic of dissimilar sandwich composite components created by acrylonitrile styrene acrylate (ASA) polymer and MgAl3Zn1 magnesium alloy were examined in detail. Real-time experimental tests were performed together with numerical efforts to understand the mechanisms. The aim was to attain lightweight, mechanically durable, and easy producable composite laminates. Therefore, ASA thermoplastic and low density MgAl3Zn1 alloy were combined. In this context, two alternative configurations of ASA/MgAl3Zn1/ASA and MgAl3Zn1/ASA/MgAl3Zn1, were fabricated depending on the other production variables. Thermoplastic sections were formed via material extrusion-based additive manufacturing (fused deposition modelling). As for the altering printing factors, filling volume was selected as infill ratios of 20%, 60%, and 100%. Metallic sections were cut to desired shapes by means of wire electrical discharge machining (WEDM), and the related layers were adhered via a strong cyanoacrylate-based binder material. To explore the mechanicak replies, uniaxial tensile, three-point bending, and free vibration behaviors were done experimentally and checked up with ANSYS-assisted simulation solutions. The main findings pointed that the average density, ultimate tensile strength, and rigidity of polymer parts stepped up substantially with rising infill ratio. At 100% infill, calculated the tensile strength reached 43.12 MPa and elastic modulus 2.26 GPa, while at 20% infill these were 25.71 MPa and 1.43 GPa, respectively. For the flexural respenses, the maximum stress in the ASA/MgAl3Zn1/ASA structure was approximately 327, 431, and 645 MPa for 20%, 60%, and 100% infill. The MgAl3Zn1/ASA/MgAl3Zn1 sequence displayed superior first natural frequency responses. Further, the obtained difference between real tests and ANSYS evaluations indicated that the proposed simulation approach can reflect accurately the mechanical and vibration responbse of the sandwich engineering components.

Multi‐material polymer sandwich structures produced by fused filament fabrication (FFF) have attracted increasing interest for applications requiring tailored stiffness, toughness, and impact resistance. Despite growing use of adhesive bonding in additively manufactured assemblies, the combined influence of material arrangement and adhesive compliance on the mechanical response of FFF‐fabricated polymer sandwiches remains insufficiently understood. The present study aims to clarify how adhesive type and layer stacking sequence interact to govern the tensile and impact behavior of multi‐material sandwich structures manufactured from acrylonitrile styrene acrylate (ASA) and polyamide 12 (PA12). Three‐ply layered specimens with different ASA—PA12 stacking configurations were fabricated by FFF and subsequently bonded using two distinct adhesive systems, namely a cyanoacrylate‐based adhesive and a polyurethane‐based adhesive. Tensile tests and drop‐tower impact experiments were conducted to evaluate mechanical performance, damage evolution, and energy absorption characteristics. Cyanoacrylate bonding resulted in the highest tensile strength and modulus for the ASA + ASA + ASA configuration, reaching 40.28 MPa (Standard Deviation, SD: 0.24) and 1180.42 MPa (SD: 4.64), respectively, whereas the polyurethane‐bonded PA + PA + PA specimen showed the highest failure strain of 10.27% (SD: 0.33). In contrast, the cyanoacrylate‐bonded PA + PA + PA configuration exhibited the lowest tensile strength and failure strain, with 23.32 MPa (SD: 2.59) and 3.47% (SD: 0.53), respectively. Under impact loading, monolithic PA12 exhibited the highest break energy of 1.27 J, while polyurethane‐bonded multilayer specimens showed consistently higher break energy values (1.01–1.15 J) than their cyanoacrylate‐bonded counterparts (0.29–0.77 J). In addition, the specific absorbed energy of the ASA + ASA + ASA configuration increased from 0.13 kJ/kg with cyanoacrylate to 0.20 kJ/kg with polyurethane. These findings highlight the importance of interfacial design in multi‐material additive manufacturing and provide practical guidance for tailoring the mechanical and impact performance of FFF‐fabricated polymer sandwich structures.

Resins printed via stereolithography are increasingly common in digital dentistry, yet the impact of production parameters on their performance remains considerable. This study examined the mechanical, tribological, and antibacterial performance of two stereolithography resins intended for restoration (white) and denture (pink) applications, selecting three different exposure times (4.5, 6, and 7.5 s) as the fabrication parameter. Compression tests showed that the white resin lost ductility with increasing exposure time, presenting statistically significant decreases in failure strain and toughness. In contrast, the pink resin maintained a stable failure strain and reached its peak energy absorption capacity at 4.5 s. Statistical analysis confirmed that the two resins responded differently to UV exposure, demonstrating that the impact of exposure time varied depending on the resin type. Furthermore, increasing exposure time significantly reduced surface roughness without a statistically significant effect on hardness. Antibacterial assessment revealed contact-mediated growth-inhibitory effects depending on strain and resin type. Accordingly, optimal exposure time was resin- and property-dependent: 7.5 s favored white resin surface quality, whereas 4.5 s maximized pink resin strength and toughness. Tailoring exposure time to both the specific resin and targeted property is crucial for enhancing the clinical longevity and structural reliability of dental applications.

This study investigates the combined effects of drilling parameters and tool features on thrust force during drilling of hybrid AA7050/CFRP stacks intended for aerospace applications. Experiments were designed using a Taguchi L16 (4²2²) orthogonal array by considering feed rate, cutting speed, drill diameter, and coating condition. Unlike most previous studies on Al/CFRP stack drilling, this work provides a layer-specific evaluation by separately analyzing the thrust-force responses of the AA7050 and CFRP layers, while also correlating force behavior with aluminum-side damage and CFRP-side delamination within a unified framework. For the aluminum layer, feed rate was the dominant factor affecting thrust force, with a contribution of 71.22%, followed by drill diameter (26.22%). For the CFRP layer, drill diameter was the most influential parameter (52.58%), followed by feed rate (43.77%). Thrust force ranged from 155.24 to 414.45 N for AA7050 and from 77.73 to 175.39 N for CFRP. Uncoated tools and higher feed rates increased thrust force, leading to poorer machining performance. Delamination in the CFRP layer was primarily governed by feed rate (46.71%), followed by drill diameter (35%). Overall, increasing feed rate and drill diameter significantly deteriorated the machinability of the hybrid structure.

Understanding the impact performance of fused deposition modeling (FDM) components is critical for their reliable application in load‐bearing and safety‐sensitive structures. This study provides a comprehensive experimental investigation into how mesostructural parameters—specifically infill ratio, infill pattern, and stacking configuration—influence the behavior of FDM‐printed PLA and PETG under impact loading. Charpy impact tests were conducted on identical‐layer and multilayered specimens fabricated with varying infill strategies, enabling a comparative evaluation of impact strength. The results demonstrate that mesostructural parameters play a more decisive role in governing impact behavior than the intrinsic properties of the base polymers. Among the tested configurations, PETG specimens with a 100% infill ratio and a trihexagon pattern achieved the highest impact strength of 32 kJ/m ² , while PLA samples with 20% infill ratio and a gyroid structure exhibited the lowest value of 16.9 kJ/m ² . The trihexagon pattern consistently provided the highest impact resistance, while zigzag and gyroid patterns performed poorly, especially at low infill ratios. Higher infill ratios enhanced absolute impact strength, whereas lower infill ratios improved specific impact strength, offering a lightweight advantage. The comparative analysis revealed that multilayered K2 configurations exhibited superior resistance to crack propagation, accompanied by a more stable fracture response relative to the K1 designs. Notably, the best specific impact strength among multilayered specimens was achieved by trihexagon‐based K1 models, reaching 31.5 J m ³ /kg m ² for PETG and 30 J m ³ /kg m ² for PLA. These findings highlight the critical role of mesostructural optimization in tailoring lightweight, high‐performance polymer components produced by additive manufacturing.

This paper analyzes the combined effects of acetone vapor treatment and 3D printing process parameters (layer thickness and infill rate) on the hardness and surface roughness of acrylonitrile styrene acrylate (ASA) components by using different machine learning and deep learning strategies for the first time in the technical literature. Considering the high-performance materials and aesthetic requirements of manufacturers, post-processing operations are highly critical for 3D-printed samples. ASA is a promising alternative, especially for the structural parts utilized in outdoor conditions like car outer components, electronic part housing, extreme sports equipment, and construction materials. However, it has to sustain hardness features against outer scratching, peeling, and indentations without losing its gloss. Together with the rising competitiveness in the search for a high-performance design with a perfect outer view, the combination of additive manufacturing and machine learning methods was implemented to enhance the hardness and surface quality properties for the first time in the literature. Concordantly, in this study, four different vaporizing durations (15, 45, 90, and 120 min.), three different layer thicknesses (0.1, 0.2, and 0.4 mm), and three different infill rates (25, 50, and 100%) were determined. According to both experimental and multi-way learning approaches, the results show that the support vector regressor (SVR) combined with one-dimensional convolutional neural networks (1D-CNNs) was the best approach for predictions. Gradient boosting (GB) and recurrent neural networks (RNNs) may also be preferable for low-error forecasting. Moreover, although there was a positive relationship between the layer thickness/infill rate and Shore D hardness outcomes, the highest levels were obtained at 45 min of vaporizing.

In recent years, the importance of recycling in mitigating harm to ecosystems and supporting sustainability has been growing worldwide. This study presents the effects of different material extrusion parameters on hardness, ultimate tensile strength (UTS), resilience, toughness, and modulus of elasticity in recycled polylactic acid (rPLA) and polyethylene terephthalate glycol (rPETG) samples produced via additive manufacturing. Regression analyses were performed to evaluate the effects of infill rate, layer height, and raster orientation. Subsequently, the samples were retested to verify the accuracy of the parameters obtained from the analysis. The most sensitive parameters for hardness were layer height and infill rate while UTS and toughness were directly proportional to the infill rate. The highest toughness, UTS and resilience values were obtained at 90° raster orientation, 0.1 mm layer height and 100% infill rate for both materials. These values were 286 MJ/m ³ , 57 MPa, and 85.5286 MJ/m ³ for rPLA and 232 MJ/m ³ , 53.8 MPa, and 139.88 MJ/m ³ for rPETG. In addition, the regression analysis revealed that the relative maximum error values for the validation sample were 10% for toughness, UTS, and resilience.

Polymer composite laminates with different core and sheet combinations are extensively adopted in the automotive and aerospace industries due to their low density, superior vibration-damping and shock absorption characteristics. This study presents the experimental and numerical analysis of the vibration behavior of sandwich tapered beams consisting of 3D printed acrylonitrile styrene acrylate (ASA) layers and AZ31B grade Mg alloy first time in the literature. First, the vibration analysis of tapered sandwich beams was conducted using the finite element method by ANSYS software. In addition, the solution approach was checked through comparison of the natural frequency values calculated from ANSYS software with literature studies. Then, the calculated natural frequencies were compared with experimental results to ensure the correctness of the numerical models. It was observed that the numerical findings showed great correspondence. Finally, we investigated in great detail how tapering angle and infill rate affected the natural frequencies of sandwich conical beams. According to the output, natural frequencies of the samples dropped as ASA’s infill rate rose. Furthermore, it was found that the natural frequency dropped when the AZ31B layer was moved nearer the center.

This study investigates the free vibration behavior of 3D-printed PA6 layered plates by considering the effects of stacking sequence, infill ratio, and boundary conditions. Unlike previous works, this research provides a comprehensive analysis combining experimental pre-analyses and finite element simulations. Nine different plate configurations with infill ratios of 40%, 70%, and 100%, and aspect ratios (a/b = 1, 1.5, 2, and 2.5) were analyzed under clamped and simply supported boundary conditions. The mechanical properties of the printed material were determined through tensile testing, and these properties were used as input for the numerical model developed in ANSYS. Before the vibration analyses, the model was validated by comparing its results with existing literature, showing close agreement. Results showed that higher infill ratios in the outer layers increase natural frequencies due to improved stiffness, whereas a denser core can reduce them due to increased mass. Additionally, increasing the aspect ratio leads to higher natural frequencies. The findings offer valuable insights for improving the vibration performance of 3D-printed PA6 components used in functional parts such as gears, fan blades, and robotic arms.