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Conventional polymeric membrane manufacturing faces significant limitations, including reliance on harsh chemicals, limited geometrical shapes (primarily flat sheets and hollow fibers), low resolution, and slow production speeds. This study introduces an innovative approach for 3D printing complex-shaped membranes with tailored properties, utilizing polymerization-induced phase separation (PIPS) and masked stereolithography (MSLA). The influence of processing parameters, including resin volume, irradiation duration, and temperature, on membrane characteristics—such as pore size, porosity, thickness, surface morphology, water permeability, and rejection rate— is systematically investigated. The findings indicate that this method can fabricate membranes with a wide range of pore sizes and porosities. The membrane architecture comprises interconnected nodules, the dimensions of which are contingent upon the processing conditions. Furthermore, the study demonstrates that PIPS facilitates the phase inversion of thermosets and the incorporation of environmentally friendly biobased solvents, thereby broadening the scope of membrane fabrication with novel polymers.

Silicon dioxide (SiO ) nanoparticles approximately 5 nm in size have been obtained. A method has been developed for introducing SiO nanoparticles into photolithographic resin at concentrations up to 0.1%. Composite resins can be used to manufacture parts with complex geometries with a maximum achievable resolution of 50 μm. Parts made from composite resin with SiO nanoparticles polish well. After polishing, areas of approximately 100 μm with height differences of less than 10 nm are revealed on the surface of the parts. A relatively uniform distribution of SiO nanoparticles is observed within the parts, and no optical defects are detected. However, areas differing in the phase shift of electromagnetic radiation are observed within the parts. Importantly, the presence of nanoparticles in the resin during MSLA printing increases the degree of resin polymerization. SiO nanoparticles have been shown to have prooxidant properties, leading to the formation of 8-oxoguanine in DNA and long-lived reactive protein species. Components made from photolithographic resins with SiO nanoparticles have been shown to inhibit the growth and development of bacteria, with a significant loss of viability. Despite their antimicrobial properties, components made from photolithographic resins with SiO nanoparticles do not affect the growth and development of mammalian cells.

The development of microtextures has had a transformative impact on surface design in engineering, leading to substantial advancements in the performance, efficiency, and functionality of components and tools. This study presents an innovative methodology for fabricating SEDM electrodes. The methodology combines additive manufacturing by mask stereolithography with an optimized electroforming process to obtain high-precision copper shells. A key aspect of the study involved redesigning the electroforming equipment, enabling the independent examination of critical variables such as anode–cathode distance and electrolyte recirculation. This approach allowed precise analysis of their impact on metal deposition. This redesign enabled the assessment of the impact of electrolyte recirculation on the quality of the shells obtained. The findings indicate that continuous recirculation at 60% power effectively reduced thickness deviation by up to 32.5% compared to the worst-case scenario, achieving average thicknesses within the functional zone of approximately 110 µm. In contrast, the absence of flow or excessive turbulence did not generate defects such as unfilled zones or non-uniform thicknesses. The shells obtained were validated as functional tools in SEDM, demonstrating their viability for the generation of textures with high geometric fidelity. This approach optimizes the manufacturing of textured electrodes and opens new opportunities for their application in advanced industrial processes, providing a more efficient and sustainable alternative to conventional methods.

This paper addresses the critical challenge of optimizing support structures and build orientation in additive manufacturing, with a focus on the fabrication of dental bridges using the Masked stereolithography (MSLA) process. The aim of this study is to minimize the support structures and optimize the building orientation. A simulation-based analysis combined with a decision-based optimization approach was implemented to evaluate the system-generated versus user-defined support structures. The simulation analysis enabled a detailed assessment of different build orientations that may affect the number of support structures and their locations. The findings indicate that the build orientation has a significant impact on the location and quantity of support structures, thus affecting material consumption and printing costs. This approach results in a 34% overall reduction in support structures compared to system-generated supports, resulting in a 13% reduction in material consumption and a 12% reduction in printing costs. The significance of this work lies in its ability to optimize the build orientation that can produce dental bridges with minimal support structures using MSLA. This research provides valuable insights for practitioners seeking to improve manufacturing efficacy and minimize support structures in dental manufacturing using 3D printing.

Additive manufacturing (AM) is a fast-growing technology that supports the rapid fabrication of prototypes. Already, employing AM technologies in early product development stages can help to accelerate the time from conceptualisation phase to the market entry. Furthermore, advances in the field of materials, such as highly transparent resins in the visible wavelength spectrum, also open application potentials for the design and fabrication of optical components. Three highly transparent resins from different suppliers are studied in this work regarding their influence on the geometrical and optical properties of additively manufactured components. The different materials were processed using a masked stereolithography 3D printer. Geometrical and optical properties of the generated test samples were analysed by means of laser scanning microscopy and spectrophotometry, respectively. A clear correlation between optical properties of the resin and the solidified samples was identified. It was further found that while spin coating does not significantly affect the geometrical properties, a strong influence on the resulting optical properties could be observed. The highest transmission properties, in the range of up to 90%, were determined for samples that were spin-coated on both surfaces. Thus, applying a spin coating operation to additively manufactured optical components is recommended for the highest transmission properties.

The paper presents research on the comparison of printouts from two different additive technologies: FDM and MSLA. Two printers were from the same producer. The paper describes the successive steps of the research and the final results. The study was carried out to determine the strengths and weaknesses of the FDM and MSLA technologies, as well as their suitability for use in unit and hobby production. The research consists of the following steps: conceptualization and design of 3D models (in Autodesk Fusion 360 2.0.12670 software), development of the survey questionnaire, expert selection, setting the printing parameters for two printers, printing process, evaluation of the printouts, and finally calculating and analyzing surveys results. The authors designed eight models; therefore, they get sixteen printouts that were the subject of comparison for experts. All cube-based models were symmetric about point, axis, and plane. The research included ten experts who were chosen on the basis of specific criteria. The research was referring to unit production. The symmetrical layout of each model on the 3D printer worktable was to verify the operation of the nozzle of this machine in relation to all axes. Moreover, the symmetry of the models made it possible to check the quality of the printouts on each side in three planes. The sum of all collected data from the surveys was 2400.

This study investigates the mechanical behavior of water-washable photosensitive resins used in masked stereolithography (mSLA) 3D printing, evaluating the effect of post-curing time (0, 5, 10, 30, and 60 min) and printing orientation (Flat [XY], Vertical [Z], and On-edge [XZ]) on the material characteristics. Specimens were manufactured according to ISO 527-2 type 1B and ISO 178 standards for tensile and bending tests, respectively. A Matlab algorithm was developed to automate the processing of experimental data. This tool enabled the extraction of parameters to fit distinct mathematical models for the elastic (linear) and nonlinear (polynomial) regimes, allowing the material response to be characterized at different curing times and print orientations. These models were implemented in Ansys Workbench for comparison with experimental results. The results show that increasing the post-curing time from 0 to 60 min raises the elastic modulus from 964.5 to 1892.4 MPa in the Flat [XY] orientation and from 774 to 1661.2 MPa in the Vertical [Z] orientation for tensile testing. In bending testing, the Flat [XY] orientation presented the best mechanical properties, while the Vertical [Z] and On-edge [XZ] orientations showed similar behavior. The numerical simulations adequately reproduced the experimental results, validating the developed constitutive models. Finally, a stress–strain correlation model is presented that enables estimation for any post-curing time between 0 and 60 min. This study provides essential data for optimizing 3D printing processes and developing structural applications with photopolymer resins.

Background The \"drive by wire\" mechanism for managing the throttle is not applied to every modern motorcycle, but it is often managed through a steel wire. Here, there is a cam on the throttle control. Its shape allows the throttle opening to be faster or slower and its angle of rotation, required for full opening, to be greater or less. The maximum angle a rider's wrist can withstand depends on numerous musculoskeletal mobility factors, often limited by falls or surgery. Methods Using a Progrip knob with interchangeable cams allows the customization of a special cam profile, to ensure the best engine response to throttle rotation and ergonomics for the rider. The use of FEA software and lattice structures, allows to realize a lightweight and efficient design, targeted for fabrication with additive manufacturing technologies. Results The cam was manufactured by exploiting MSLA technology. Finally, a dimensional inspection procedure was performed before assembly. The main result is to have obtained a lighter and cheaper component than the original. Conclusions This study has allowed the design of a mechanical component consisting of innovative shape, light weight, and ergonomics. Furthermore, it demonstrates the effectiveness in the use of lattice structures to enable weight optimization of a component while minimizing the increase in its compliance.

Purpose Different technologies may currently be used to produce dental prostheses, such as additive manufacturing and traditional milling. This study aims to evaluate and improve the fabrication process for hot-pressed porcelain dental prostheses and compare the use of masked stereolithography apparatus (MSLA) casting to computer-aided design/computer-aided manufacturing (CAD/CAM) casting. The cost-benefit analysis of producing dental prostheses through various technologies, including additive manufacturing and traditional milling, has not been fully explored. The cost of materials and processes used to produce prostheses varies based on complexity of design and materials used, and long-term effects, such as durability and wear and tear, must be taken into account. Design/methodology/approach Using key elements of part costs and estimation cost models, a multivariable approach was used to evaluate the practicality of the recommended strategy and process improvement. Findings The research found that MSLA casting provides a higher return on investment than CAD/CAM casting, and the optimized production process could be more suitable for the size and annual demand for prostheses. Originality/value Overall, this study highlights the need for a more comprehensive understanding of the cost-benefit analysis of different dental prosthesis production methods and emphasises the importance of evaluating long-term effects on the cost-benefit analysis.

Background: The \"drive by wire\" mechanism for managing the throttle is not applied to every modern motorcycle, but it is often managed through a steel wire. Here, there is a cam on the throttle control. Its shape allows the throttle opening to be faster or slower and its angle of rotation, required for full opening, to be greater or less. The maximum angle a rider's wrist can withstand depends on numerous musculoskeletal mobility factors, often limited by falls or surgery. Methods: Using a Progrip knob with interchangeable cams allows the customization of a special cam profile, to ensure the best engine response to throttle rotation and ergonomics for the rider. The use of FEA software and lattice structures, allows to realize a lightweight and efficient design, targeted for fabrication with additive manufacturing technologies. Results: The cam was manufactured by exploiting MSLA technology. Finally, a dimensional inspection procedure was performed before assembly. The main result is to have obtained a lighter and cheaper component than the original. Conclusions: This study has allowed the design of a mechanical component consisting of innovative shape, light weight, and ergonomics. Furthermore, it demonstrates the effectiveness in the use of lattice structures to enable weight optimization of a component while minimizing the increase in its compliance.