Optimization of 3D‐Printed Structured Packings—Current State and Future Developments

PurposeSkin cancer is the most common tumor in the population. There are different therapeutic modalities. Brachytherapy is one of the techniques used, in which it is necessary to build customized moulds for some patients. Currently, these moulds are made by hand using rudimentary techniques. We present a new procedure based on 3D printing and the analysis of the clinical workflow.Material and methodsMoulds can be made either by hand or by automated 3D printing. For making moulds by hand, a patient’s alginate negative is created and, from that, the gypsum cast and customized moulds are made by hand from the patient’s negative template. The new process is based on 3D printing. The first step is to take a 3D scan of the surface of the patient and then, 3D modelling software is used to obtain an accurate anatomical reconstruction of the treatment area. We present the clinical workflow using 3D scanning and printing technology, comparing its costs with the usual custom handmade mould protocol.ResultsThe time spent for the new process is 6.25 hours, in contrast to the time spent for the conventional process, which is 9.5 hours. We found a 34% reduction in time required to create a mould for brachytherapy treatment. The labor cost of the conventional process is 211.5 vs. 152.5 hours, so the reduction is 59 hours. There is also a 49.5% reduction in the financial costs, mostly due to lack of need of a computed tomography (CT) scan of the gypsum and the mould. 3D scanning and printing offers financial benefits and reduces the clinical workload.ConclusionsAs the present project demonstrates, through the application of 3D printing technologies, the costs and time spent during the process in the clinical workload in brachytherapy treatment are reduced. Overall, 3D printing is a promising technique for brachytherapy that might be well received in the community.

To reduce the carbon footprint of manufacturing processes, it is necessary to reduce the number of stages in the development process. To this end, integrating additive manufacturing processes with three-dimensional (3D) printing makes it possible to eliminate the need to use tooling for component manufacturing. Furthermore, using 3D printing allows the generation of complex models to optimize different components, reducing the development time and realizing lightweight structures that can be applied in different industries, such as the mobility industry. Printing process parameters have been studied to improve the mechanical properties of printed items. In this regard, although the failure of most structural components occurs under dynamic load, the majority of the evaluations are quasistatic. This work highlights an improvement in fatigue strength under dynamic loads in 3D-printed components through heat treatment. The fatigue resistance was improved regarding the number of cycles and the dispersion of results. This allows 3D-printed polylactic acid components to be structurally used, and increasing their reliability allows their evolution from a prototype to a functional component.

Textiles are an essential part of human lives and are associated with them from cradle to grave. There is a limitless choice of materials, processes, designs, and applications of fibers and textiles. However, conventional textile processing uses considerable resources and is not always environment friendly. Three-dimensional (3D) printing offers new avenues and provides a considerable value in addition to textile materials. From simple printing of designs or patterns, complex structures such as wearable electronics and space textiles are made using 3D technology. Similarly, the creation of nanostructures, self-colored clothing, and imparting functional finishes are also done through 3D printing. Innovative smart textiles that contain bioactive agents, carbon nanotubes, etc. which can provide high-performance properties, improve appearance or durability, which can be done using 3D printing. One such example is of temperature-regulated clothing developed using 3D printing. In this chapter, we will provide an overview of the opportunities and the challenges of 3D printing in fashion and textiles. Examples include the application of 3D printing in medical textiles, industrial textiles, jewelry, and fashion. Most 3D-printing 190technologies are done using synthetic polymers such as nylon, polyester, poly(lactic acid), and thermoplastic polyurethane. Possibilities of developing 3D-printed objects using natural polymers or other additives have been discussed.

Advances in Computer aided design (CAD), modeling and Three-dimensional (3D) printing has led to paradigm shift in development of innovative and miniaturized explosive devices for armament applications. In conventional techniques, explosives are either pressed or casted and machined to required geometry. These conventional processes are mostly manual and monotonous; require high-cost tooling and the lead-time from concept to product is high. 3D printing is an automated additive manufacturing process in which the material is deposited layer-by-layer to build physical part with any intricate geometry and profile, from the CAD model of the part. 3D printing of explosive devices offers advantages of computer aided design techniques, automation, direct physical part fabrication, low lead-time, low cost and any geometrical shape can be printed. It also offers advantage of printing explosive parts in the battlefields. In this paper, along with the detailed review of future trends in 3D printing of armament and explosive devices, a case study of 3D printing of plastic bullets in Acrylonitrile Butadiene Styrene (ABS) material is presented. The plastic bullets are used in low intensity conflicts and riot control. The experimental firing trials were conducted using standard AK- 47 gun firing on Gelatin target blocks placed at 30 m distance from the muzzle of the gun. The trials showed performance of ABS bullets in terms of lethality and velocity drop comparable to existing plastic bullets made of Nylon-66 manufactured by injection molding process. 3D printed ABS bullets have advantage of batch-to-batch repeatability, high accuracy. 3D printing is revolutionizing the way armament and explosive devices are manufactured, performance improvement and miniaturization.

The decision on whether to proceed to top-down or bottom-up during software development has a strong and underestimated impact on the quality of the final product including its later evolvability. Various examples for both strategies taken from such different domains as operating systems and computer games provide evidence that bottom-up developed systems are more suitable for future evolution. The reasons for this range from the increased compositionality of bottom-up developed artefacts at the technical level up to a greater independence from certain requirements which constitute the most transient part of a software system. Besides those advantages concerning evolvability, the negative effects of bottom-up orientation can not be ignored. Furthermore, proceeding bottom-up contradicts most conventional development processes. We regard this as a clear indication for the need of new development processes to improve the construction of evolvable software.

The influence of particle shape on disordered packing structures is investigated through a combined experimental and modeling approach, focusing on non-equant particles, i.e. particles which are either elongated or flat, or both. In an experimental campaign, particles of systematically chosen shapes are fabricated via 3D printing, then packed and imaged by X-ray Computed Tomography to extract packing properties such as the porosity, particle orientations, and tortuosities of paths through the pore space. Additionally, a Monte Carlo model is employed to simulate packing structures, allowing for broader exploration of the parameter space, and investigating properties which are challenging to measure experimentally. The model’s parameters are varied to probe the range of potential packing structures for various particle shapes, and to provide explanations for experimental results. Both model and experiments reveal a non-monotonic trend for the porosity, a monotonically decreasing trend for the average particle inclination, and a monotonically increasing trend for the tortuosity with respect to elongation and flatness. Additionally, both model and experiments show increased dependence of the packing properties on the packing method (pouring or shaking), or model parameters respectively as particle aspect ratio increases. Furthermore, the model can predict experimentally measured packing porosities with deviations of 0.03 in absolute porosity units at most for new particle shapes, once its parameters are fitted to match the physical context. This research provides insights into the effect of particle shape on packing structure, with practical implications to processes involving the packing of non-equant particles, such as crystal filtration and packed beds.

3D Printer is expected as a major tool for additive manufacturing. However, almost all components made by 3D printers are used to investigate shapes of some product, and it still not work as machine elements to drive some machines. In gear manufacturing, 3D printer hardly applied to make gears because of the strength and precision issues. In this study, the authors try to build some test gears with using 3D printer for the purpose of simplifying gear manufacture. The test gears are built in several different laminating angles, and measured there tooth profile errors and pitch errors. Then the authors compared those 3D printer-made gears with hobbed gear in accuracy. In conclusion, when using 3D Printer to build a gear, its layers would be piled up vertically to its gear shaft to reduce tooth profile errors and pitch errors.

Three‐dimensional (3D) printing has the potential to revolutionize the way energy storage devices are designed and manufactured. In this paper, we explore the use of 3D printing in the design and production of energy storage devices, especially zinc‐ion batteries (ZIBs) and examine its potential advantages over traditional manufacturing methods. 3D printing could significantly improve the customization of ZIBs, making it a promising strategy for the future of energy storage. In particular, 3D printing allows for the creation of complex, customized geometries, and designs that can optimize the energy density, power density, and overall performance of batteries. Simultaneously, we discuss and compare the impact of 3D printing design strategies based on different configurations of film, interdigitation, and framework on energy storage devices with a focus on ZIBs. Additionally, 3D printing enables the rapid prototyping and production of batteries, reducing leading times and costs compared with traditional manufacturing methods. However, there are also challenges and limitations to consider, such as the need for further development of suitable 3D printing materials and processes for energy storage applications.

An improved marine predators algorithm for shape optimization of developable Ball surfaces

Since its invention in the 1980s, 3D printing has evolved into a versatile technique for the additive manufacturing of diverse objects and tools, using various materials. The relative flexibility, straightforwardness, and ability to enable rapid prototyping are tremendous advantages offered by this technique compared to conventional methods for miniaturized and microfluidic systems fabrication (such as soft lithography). The development of 3D printers exhibiting high printer resolution has enabled the fabrication of accurate miniaturized and microfluidic systems—which have, in turn, substantially reduced both device sizes and required sample volumes. Moreover, the continuing development of translucent, heat resistant, and biocompatible materials will make 3D printing more and more useful for applications in biotechnology in the coming years. Today, a wide variety of 3D‐printed objects in biotechnology—ranging from miniaturized cultivation chambers to microfluidic lab‐on‐a‐chip devices for diagnostics—are already being deployed in labs across the world. This review explains the 3D printing technologies that are currently used to fabricate such miniaturized microfluidic devices, and also seeks to offer some insight into recent developments demonstrating the use of these tools for biotechnological applications such as cell culture, separation techniques, and biosensors.

Purpose The utilization of three-dimensional (3D) printing in composite materials reduces constraints and opens new possibilities for the development of protective textiles compared to conventional manufacturing processes. Previous studies have predominantly focused on investigating critical parameters that influence the adhesion quality of 3D printed layers on textile substrates, along with the structural characteristics of two-dimensional (2D) textile substrates. However, 3D fabrics with superior properties have not been extensively explored. This study aims to develop innovative 3 days printing auxetic structure–spacer fabric composites with enhanced protection and comfort. Design/methodology/approach Using an entry-level Fused Deposition Modeling (FDM) printer, polymer materials were directly deposited onto 3D spacer fabrics. A series of printing trials determined the optimal process parameters, after which composites with various tilting angles were fabricated. Their deformation behavior and energy absorption characteristics were then evaluated through systematic compression tests. Findings It is found that Thermoplastic Polyurethane (TPU) is more suitable for composite with spacer fabrics compared to Polylactic Acid (PLA). Optimal printing conditions were identified as a speed of 30–40 mm/s, a preheating temperature of approximately 209 °C and an extrusion temperature between 215 and 220 °C. Additionally, an appropriate Z-axis distance effectively combines the 3D printed components with the fabric while maintaining the comfort of the spacer fabric. Composites with a 45°tilting angle demonstrated the best compressive and energy absorption performance under 80 and 50% strain conditions. Practical implications The composites we fabricated with a single-layer thickness below 9 mm, especially the 45° tilting angle structure is only about 7 mm, meeting dimensional requirements for protective equipment (e.g. helmet liners and protective pads). Additionally, the uniform microporous array on the composites surface enhancing breathability without compromising surface smoothness, and contributing to improve comfort in wearable protective applications. The good performance in compressive strength and energy absorption capacity underscoring its potential in applications requiring efficient energy absorption at low strain, such as protective padding and sportswear components. Social implications The increasing demand for personal safety protection has driven the development of high-performance textile composites. Personal protective equipment must not only provide excellent protective functionality but also ensure comfort and portability. Composites with multifunctional gradually replace traditional textiles by balancing protection, flexibility and wearer comfort. Moreover, flexibility of 3D printing can meet the needs of different markets for customization of high-performance personal protective equipment. Originality/value These findings demonstrate the potential of composite materials in applications requiring high energy absorption at low strain conditions and also reflect the promise of integrating FDM 3D printing technology with spacer fabrics for the design and manufacturing of advanced auxetic materials for personal protective equipment.

Fracture behavior of intact and defected 3D-printed parts

Steam boiler mixing channel optimization with a surrogate based multi objective genetic algorithm

The growing demand for sustainable rapid tooling in 3D printing highlights the requirement for such advanced materials that are designed using the framework of green chemistry principles. The application of rapid tooling in 3D printing has driven the need for advanced materials with high strength and thermal stability. Reinforcing thermoplastics like acrylonitrile butadiene styrene (ABS) along with nanomaterials such as graphene has the potential for improving the processability in 3D printing, along with its mechanical properties. This study mainly aims for developing ABS reinforced with graphene‐based feedstock filament by using the fused filament fabrication (FFF) process for applications related to 3D printing. Initially, by using the Taguchi L9 orthogonal array, the fabrication of the ABS‐graphene‐based filaments was done by varying the factors like composition of graphene (1% weight, 1.5% weight, and 2% weight), temperature during extrusion (200°C, 205°C, and 210°C), and speed of the screw during extrusion (3, 6, and 9 rpm). Then, the prepared samples of the filaments were subjected to various tests like tensile testing, followed by morphological analysis (SEM and surface roughness tests), thermal stability (TGA), and chemical bonding (FTIR) analysis. On further inspection, the filament with 2% weight of graphene powder and 210°C as the temperature of extrusion at an extrusion speed of 3 rpm was found to be the most optimized one. Hence, the results revealed that there was a significant improvement in the values of Young’s modulus and enhanced homogeneity of structure, with better thermal properties as compared to the pure ABS‐based filament. The improved stiffness, thermal stability, and smooth extrusion behavior of the developed filaments under MEX conditions demonstrate their suitability for rapid tooling applications that require dimensional stability and rigidity. Apart from the thermal stability and enhanced stiffness, the graphene‐based proposed polymeric filaments can reduce waste with improved energy efficiency and offer potential catalytic functionalities. Thus, it contributes to additive manufacturing and aligns the goals with green chemistry principles.

Three-dimensional (3D) printing has transformed the development of microneedle arrays (MNAs) by enabling exceptional control over their geometry, distribution, materials, and functionality in a single-step, customizable process. This review represents a design-centric framework that organizes recent advancements in four interconnected levers: (i) individual microneedle (MN) geometry and size; (ii) patch-level MN distribution and multi-array architectures; (iii) computer-aided design (CAD), finite element analysis (FEA), computational fluid dynamics (CFD), and artificial intelligence/machine learning (AI/ML)-driven optimization; and (iv) manufacturing constraints and emerging solutions for scalability and reproducibility. Outcomes show that small changes in the radius of the MN’s tip, the MN’s aspect ratio, the MN’s internal lattice architecture, and the spacing of the array can dramatically influence their insertion force, mechanical reliability, payload capacity, and therapeutic coverage. Now, digital tools can bridge the design and experimental outcomes, while novel morphologies, hybrid materials, and theranostic integrations are expanding the clinical potential of MNs. The remaining challenges, resolution-versus-throughput trade-offs, biocompatibility, batch-to-batch consistency, and lack of testing standardization are examined alongside promising directions in high-throughput 3D printing, stimuli-responsive materials, and closed-loop systems. Finally, rational, model-guided design strategies are positioning 3D-printed MNAs as versatile platforms for painless, patient-specific drug delivery, diagnostics, and personalized medicine.