Printing Time Research Articles

Cost estimation and performance evaluation of 3D printed membranes for vanadium redox flow batteries

AbstractThe membrane is a central component in the commercialization of vanadium redox flow batteries (VRFB), with Nafion being the preferred material for those membranes. Nafion suffers however from high vanadium crossover and high cost, thus limiting its wider commercial application in VRFB. To address this, studies have focused on sulfonated polyether ether ketone (SPEEK) as an alternative material. This work presents an economic study on the production costs of 3D printed SPEEK (3D‐SPEEK) membranes for VRFB, with multiple production scenarios evaluated. This analysis relies on the performances of 3D‐SPEEK membranes prepared in our laboratory, which have shown higher Coulombic efficiency and lower vanadium ions diffusion than Nafion membranes. Results from the economic analysis revealed that the cost of the 3D‐SPEEK membrane varies from 567.77 to 79.35 €/m2 depending on the production scheme and scale used. Production costs lower than commercial Nafion membranes are achieved when a large production scheme is used. Further analysis shows that 3D‐SPEEK membranes might even be cheaper than conventional SPEEK membranes if their printing time is reduced.

3D Printing of Individualized Microfluidic Chips with DLP-Based Printer

Microfluidic chips have shown their potential for applications in fields such as chemistry and biology, and 3D printing is increasingly utilized as the fabrication method for microfluidic chips. To address key issues such as the long printing time for conventional 3D printing of a single chip and the demand for rapid response in individualized microfluidic chip customization, we have optimized the use of DLP (digital light processing) technology, which offers faster printing speeds due to its surface exposure method. In this study, we specifically focused on developing a fast-manufacturing process for directly printing microfluidic chips, addressing the high cost of traditional microfabrication processes and the lengthy production times associated with other 3D printing methods for microfluidic chips. Based on the designed three-dimensional chip model, we utilized a DLP-based printer to directly print two-dimensional and three-dimensional microfluidic chips with photosensitive resin. To overcome the challenge of clogging in printing microchannels, we proposed a printing method that combined an open-channel design with transparent adhesive tape sealing. This method enables the rapid printing of microfluidic chips with complex and intricate microstructures. This research provides a crucial foundation for the development of microfluidic chips in biomedical research.

Optimization of Infill Density, Layer Height, and Shell Thickness to Achieve Maximum Bending Strength and Minimum Printing Time of PLA 3D Printed Part

3D printing has advantages in making customized products, such as leg prosthetics. One of the required properties of 3D-printed leg prosthetics is their resistance to bending stress. Based on the literature review, the influence of the interaction among layer height, infill density, and shell thickness on the bending strength and printing time has not yet been investigated or optimized. This study aims to investigate the effect and optimize the layer height, infill density, and shell thickness to achieve the maximum bending strength and minimum printing time of a Polylactic Acid 3D printed part. This research studies three independent variables: layer height, infill density, and shell thickness. The independent variables of this research are bending strength and printing time. The bending test is conducted according to the ISO 178 standard. The printed specimen is tested using the bending testing machine Tarno Grocki to measure the maximum bending load the specimen can hold. The printing time is measured by using a stopwatch. The Response Surface Method is used as an optimization method to find the value of the maximum bending strength and minimum printing time of the 3D printed part. The optimum responses are achieved using 40 % infill density, 0.3 mm layer height, and 1.6 mm shell thickness. The maximum bending strength is 118. 5129 MPa and the minimum printing time is 11.1867 minutes.

Voxel-based variable width continuous spiral path planning for 3D printing

Discontinuous printing paths in 3D printing lead to wasted time in fabricating products. This paper proposes a voxel-based continuous spiral path planning algorithm for 3D printing parts with less time consumption. Interestingly, we found our method can also improve the surface qualities and mechanical properties of the printed parts. The proposed path planning strategy in this paper is based on voxels which is different from traditional path planning strategies in literature. Firstly, our proposed algorithm determines the voxel size by considering the printable width of the printer nozzle. It then generates discrete elements by voxelizing the model and creates spirals and line segments by restricting the print direction of the connectable discrete elements. Next, the algorithm employs the Euler circuit to generate continuous sub-paths for the spirals and line segments. It utilizes the depth-first traversal algorithm to traverse and open the continuous sub-paths, resulting in printable continuous paths. To maintain surface accuracy for complex models, contour lines are introduced on the model's exterior and connected internally to ensure global path continuity. Lastly, the algorithm controls the path width in different directions by adjusting the extrusion rate of the printhead, preventing path overlap. Experimental results demonstrate that the proposed algorithm outperforms traditional path planning algorithms and the Connected Fermat spirals algorithm. The proposed strategy effectively mitigates the negative effects of path discontinuity, reduces printing time, and improves printed accuracy, and mechanical properties.

3D printing as a pedagogical tool for teaching normal human anatomy: a systematic review

BackgroundThree-dimensional-printed anatomical models (3DPAMs) appear to be a relevant tool due to their educational value and their feasibility. The objectives of this review were to describe and analyse the methods utilised for creating 3DPAMs used in teaching human anatomy and for evaluating its pedagogical contribution.MethodsAn electronic search was conducted on PubMed using the following terms: education, school, learning, teaching, learn, teach, educational, three-dimensional, 3D, 3-dimensional, printing, printed, print, anatomy, anatomical, anatomically, and anatomic. Data retrieved included study characteristics, model design, morphological evaluation, educational performance, advantages, and disadvantages.ResultsOf the 68 articles selected, the cephalic region was the most studied (33 articles); 51 articles mentioned bone printing. In 47 articles, the 3DPAM was designed from CT scans. Five printing processes were listed. Plastic and its derivatives were used in 48 studies. The cost per design ranged from 1.25 USD to 2800 USD. Thirty-seven studies compared 3DPAM to a reference model. Thirty-three articles investigated educational performance. The main advantages were visual and haptic qualities, effectiveness for teaching, reproducibility, customizability and manipulability, time savings, integration of functional anatomy, better mental rotation ability, knowledge retention, and educator/student satisfaction. The main disadvantages were related to the design: consistency, lack of detail or transparency, overly bright colours, long printing time, and high cost.ConclusionThis systematic review demonstrates that 3DPAMs are feasible at a low cost and effective for teaching anatomy. More realistic models require access to more expensive 3D printing technologies and substantially longer design time, which would greatly increase the overall cost. Choosing an appropriate image acquisition modality is key. From a pedagogical viewpoint, 3DPAMs are effective tools for teaching anatomy, positively impacting the learning outcomes and satisfaction level. The pedagogical effectiveness of 3DPAMs seems to be best when they reproduce complex anatomical areas, and they are used by students early in their medical studies.

Sustainable Polyhydroxyalkanoate Production from Food Waste via Bacillus mycoides ICRI89: Enhanced 3D Printing with Poly (Methyl Methacrylate) Blend.

In view of implementing green technologies for bioplastic turning polices, novel durable feedstock for Bacillus mycoides ICRI89 used for efficient polyhydroxybutyrate (PHB) generation is proposed herein. First, two food waste (FW) pretreatment methods were compared, where the ultrasonication approach for 7 min was effective in easing the following enzymatic action. After treatment with a mixture of cellulase/amylases, an impressive 25.3 ± 0.22 g/L of glucose was liberated per 50 g of FW. Furthermore, a notable 2.11 ± 0.06 g/L PHB and 3.56 ± 0.11 g/L cell dry eight (CDW) over 120 h were generated, representing a productivity percentage of 59.3 wt% using 25% FW hydrolysate. The blend of polyhydroxybutyrate/poly (methyl methacrylate) (PHB/PMMA = 1:2) possessed the most satisfactory mechanical properties. For the first time, PHB was chemically crosslinked with PMMA using dicumyl peroxide (DCP), where a concentration of 0.3 wt% had a considerable effect on increasing the mechanical stability of the blend. FTIR analysis confirmed the molecular interaction between PHB and PMMA showing a modest expansion of the C=O stretching vibration at 1725 cm-1. The DCP-PHB/PMMA blend had significant thermal stability and biodegradation profiles comparable to those of the main constituent polymers. More importantly, a 3-Dimetional (3D) filament was successfully extruded with a diameter of 1.75 mm, where no blockages or air bubbles were noticed via SEM. A new PHB/PMMA "key of life" 3D model has been printed with a filling percentage of 60% and a short printing time of 19.2 min. To conclude, high-performance polymeric 3D models have been fabricated to meet the pressing demands for future applications of sustainable polymers.

A novel approach to the manufacture of dissolving microneedles arrays using aerosol jet printing

Despite much research over the last few decades, microneedle arrays for the transdermal delivery of drugs have failed to live up to their initial promise. This may be changing however as companies close in on the commercial delivery of vaccines via this technology. These breakthroughs will undoubtably increase the interest in the use of microneedles arrays for the delivery of biopharmaceuticals but will also drive research into the development of scalable manufacturing processes for their fabrication. While 3D printing is an exciting development in this field, conventional Additive Manufacturing (AM) techniques are unsuitable for biopharmaceuticals due to the harsh processing conditions which can cause degradation of the active ingredient.In this paper we report the first use of Aerosol Jet Printing (AJP) as an AM technique for the fabrication of dissolving microneedle arrays. A formulation of poly(vinyl pyrrolidone), trehalose and glycerol dissolved in water was prepared and characterised. The formulation was aerosolised using ultrasonication and deposited onto a silicon substrate. Critical process parameters such as Computer Aided Design (CAD) design, flow rate, temperature, print speed and focussing ratio were studied to determine their impact on the microneedle quality attributes. 4 × 4 microneedle arrays were printed, with needle heights > 500 µm achieved with print times of 30 mins or less. The resulting needles had sufficient strength and sharpness to penetrate porcine skin samples. Importantly, the microneedles can be fabricated under benign conditions which should be suitable for the processing and subsequent delivery of biopharmaceuticals across the skin.

Experimental investigation of the effect of the PDMS material’s oxygen- permeable window geometry on layerless uniform 3D printing

ABSTRACT One of the fundamental issues in additive manufacturing processes is layer-by-layer printing, which influences printing time and part surface quality. One way to overcome this difficulty is continuous liquid interface production (CLIP), which has enabled the mass manufacture of polymer components through continuous printing. Due to a limitation in access to this system, different oxygen gas permeable windows composed of polydimethylsiloxane polymer with variable substrate shapes were introduced and evaluated in this research. The aim of this study is to improve the printing speed of porous components in a layerless uniform 3D printing system as compared to Digital light processing (DLP). The results of these experiments show that the island container, compared to the micro-channel container, has a 107% increase in the duration of continuous printing before the separation force begins, enhances the component’s look, increases the height of the printed part by 30%, and decreases the maximum separation force by 7.4 times.

Influence of temperature on rheological properties during early‐stage geopolymerization

AbstractMetakaolin geopolymers have gained much interest as a large‐scale, 3D printable material. It is well known that increasing temperature can expedite the geopolymerization reaction, but little is known about how the temperature variability of the printing environment can influence the rheology of fresh geopolymer pastes. In this study, the influence of temperature on the viscosity of potassium geopolymer pastes was investigated under constant shearing at rates of 25, 50, or 100 s−1, yield stress measurements, and oscillatory motion. The temperature range examined was 5°C–55°C, in systematic 5°C increments. It was found that temperatures above 30°C resulted in lower starting viscosities compared to colder temperatures, but eventually exhibited an exponential increase in viscosity as the geopolymerization chemical reaction became dominate. In addition, a higher shear rate delayed, but did not stop, the exponential increase in viscosity from occurring. Yield stress values also reflected an upward trend with increasing temperatures after a 30‐min temperature soak. Lastly, oscillatory measurements indicated that viable printing times for 50°C or above were as little as 50–60 min total and were compared to Vicat needle testing. Overall, the influence of temperature on rheological properties could be used to manipulate the geopolymer viscosity for optimum printing conditions.

Theoretical Model for Carbon Footprint Calculus Based on Energy Consumption for Polymer Additively Manufactured Parts

The environmental sustainability of the additive manufacturing (AM) process has been a trend in recent years. As well as the adoption of the AM process in traditional manufacturing environments to take advantage of the customization offered by this technology. Similar studies proposed the AM environmental sustainble analysis from a life cycle, circular economy and recycled material perspective. This study is centered in the environmental evaluation of the AM process adoption. The aim of this research is to characterize a model to predict the carbon footprint in an additively manufactured piece through the energy consumption in the printing process. Pieces with different shapes and positions were simulated using a printing simulator to test the model in a fused deposition modeling 3D printer and demonstrate the impact of different manufacturing strategies. The results show that the model proposed is capable of estimating the carbon footprint through the printing time and build volume of a given piece and predict the best printing position to diminish the CO2 emission in the process. Moreover, the model proposed allows managers and practitioners to analyze multiple fabrication scenarios for decision-making.

Soluble vs Non-Soluble Support Materials for Bone 3D Printed Anatomical Models: A Comparison on Production Time, Cost and Finish Quality

3D anatomical models play an increasing important role in the 3D surgical planning area allowing specialists to have an anatomical representation of the patient before the intervention. The support material to print models is fundamental to ensure optimal finishing, which is why soluble support is a good option for these cases. BVOH (butanediol vinyl alcohol copolymer) is a water-soluble thermoplastic optimized for support generation on FDM (fuse deposition modelling) printing process. In addition, PVA (polyvinyl acetate) is another well-known soluble thermoplastic used for support generation. Compared to PVA, BVOH has some benefits and improvements such as better surface quality, solubility times and ease of printing resulting in a better finish of the model. In this study, we have compared the time and cost of printing the same case combining PLA or ABS with BVOH for the generation of support material and the same printing with supports of the same printing material. The obtained results show an increase in cost and printing time of 33 % with respect to printing with conventional supports. However, this increase in cost and time is offset by the finishes obtained; obtaining much better results compared to the use of non-soluble material to generate the support. It also represents an increase in productivity since for the post-processing of the piece it is only necessary to leave it in water for approximately 22min at a temperature of 50°C or 45min at a water temperature of 22°C. Moreover, compared to PVA, BVOH has shorter solubility times.Furthermore, in the cases where it is necessary to generate internal support, soluble support is the best option since it will be removed with water without leaving visible marks.In conclusion, the use of soluble support presents a clear advantage in terms of finish and increased performance of the 3D printing staff (i.e reduce the time that a person needs to speed removing non-soluble support material), but on the other hand, it presents an increase in cost and printing time.

Parametric Study of Functional Components Obtained by Additive Manufacturing Fused Filament Fabrication

Fused Filament Fabrication (FFF) is a growing additive manufacturing technology for various applications in the engineering field. The mechanical properties of 3D printed materials in FFF technology depends on various parameters and the literature suggests that infill pattern and infill density are the parameters that most affect the mechanical properties of 3D printed parts.These factors have direct influence on the time of production and amount of material used. In this work it was analyzed the influence of infill parameter on stiffness of the final parts, considering the printing time and amount material used. For this purpose, the Taguchi method was used and then the statistical method of ANOVA to calculate the influence of each parameter.Test specimens were printed according to ASTM Standard D790 dimensions, in Polyethylene terephthalate glycol (PETG). The specimens were printed in the same position on the printing bed to reduce as much as possible the influence of external factors on the results. A visual and dimensional inspection of the specimens was carried out for further analysis. The best combination between production and stiffness, with 350 MPa/mm, was obtained with 15% infill density, concentric pattern, 45º orientation, with 4 perimeters path, layer thickness of 0.1 mm and speed of 45 mm/s. The results obtained allow us a broader view of how to save 3D printing time and the amount of material consumed during the production of a part.

Dosimetric Validation of 3D-Printed Bolus at Different Printing Infill Percentage in VMAT Plan

The 3D printed bolus technology is rapidly evolving in external beam radiotherapy and printing parameters can have a significant impact on absorbed dose. In this study, a novel 3D printed bolus was designed to evaluate the time and material cost effects, dosimetry differences, and surface dose modulation capabilities in the volumetric-modulated arc therapy (VMAT) plan at different print filling percentages. A hollow-type bolus, the middle 2.36 mm of 5 mm thickness infilled with different ratio, was designed and printed with polylactic acid (PLA). The ratio of printed material was defined by the infill percentage parameter ranging from 10% to 90%. For each bolus, two treatment plans were designed with AAA algorithm, considering the real computed tomography (CT) scan of the 3D printed bolus and modeling the 3D printed bolus as a virtual bolus structure. Percentage depth dose (PDD) profiles were calculated to build up the mapping equivalent CT value in treatment plan system (TPS). Measurement dose was performed by radiographic films. The PDD profiles were then compared between measured and calculated. A simulation VMAT treatment plan with planning target volume (PTV) close to the body surface was designed on a water-equivalent phantom, and the modulation capabilities of epidermal dose under different filling percentage was compared. Compared with 100% percent infill 3D printed bolus, The maximum printing time could be reduced by 47.8% and material consumption could be reduced by 42.5%. The surface dose at single field irradiation can reach 69.6% to 85.8% of the maximum dose in different filling boluses. The PDD measurement and mapping equivalent CT calculation deviation was less than 3% when the infill percentage of the middle region is greater than 30%. The dose distribution of the VMAT plan is satisfying for infill percentages greater than 30%. Using the 3D printing technology is possible to modulate the amount of shift of the build-up region by tuning the infill percentage of the 3D printed bolus. Patients could undergo CT simulation without bolus. Appropriate bolus could be selected according to the location of the PTV region and dose requirement.

Bringing Medical Model Scans into Reality through 3D Printing: Materials and Manufacturing Parameters

3D printing is emerging in the healthcare field. Being able to reproduce organ models with low-cost and sustainable technology is generating a big impact on professionals working in the medical industry. This work aims to illustrate the potential of the material extrusion technique by replicating 3D models used for helping surgeons in pre-operative planning. The properties of a standard thermoplastic PLA for 3D printing are compared with other thermoplastics with elastomeric properties whose application is arising nowadays in this field, namely PEBA, TPO, and TPU. This research covers three real cases of study: a pulmonary fistula, a bone tumor, and a replication of the spinal column. The cases helped anticipate potential problems during surgery and achieve good quality in educating and training new professionals. Finally, an optimal printing configuration is presented. The settings of the printing parameters selected are the ones that maximize the inter and intra-layer bonding, which is important to achieve good shape results and consistency of the models. Although the printed parts are not meant to support a big mechanical effort, it is important to relate the selection of the printing parameters to the adhesion of filaments in order to reduce the quantity of material deposited during the manufacturing process, and consequently, reduce the printing time. Also, to achieve a realistic model that can be of effective help for the medical faculty when preparing their interventions and during their diagnostic process.

Multi-objective numerical optimization of 3D-printed polylactic acid bio-metamaterial based on topology, filling pattern, and infill density via fatigue lifetime and mass.

Infill parameters are significant with regard to the overall cost and saving material while printing a 3D model. When it comes to printing time, we can decrease the printing time by altering the infill, which also reduces the total process extent. Choosing the right filling parameters affects the strength of the printed model. In this research, the effect of filling density and infill pattern on the fatigue lifetime of cylindrical polylactic acid (PLA) samples was investigated with finite element modeling and analysis. This causes the lattice structure to be considered macro-scale porosity in the additive manufacturing process. Due to the need for multi-objective optimization of several functions at the same time and the inevitable sacrifice of other objectives, the decision was to obtain a set of compromise solutions according to the Pareto-optimal solution technique or the Pareto non-inferior solution approach. As a result, a horizontally printed rectangular pattern with 60% filling was preferred over the four patterns including honeycomb, triangular, regular octagon, and irregular octagon by considering the sum of mass changes and fatigue lifetime changes, and distance from the optimal point, which is the lightest structure with the maximum fatigue lifetime as an objective function with an emphasis on mass as an important parameter in designing scaffolds and biomedical structures. A new structure was also proposed by performing a structural optimization process using computer-aided design tools and also, computer-aided engineering software by Dassault systems. Finally, the selected samples were printed and their 3D printing quality was investigated using field emission scanning electron microscopy inspection.

Controlling anisotropy and brittle-to-ductile transitions by varying extrusion width in short fibre reinforced additive manufacturing

PurposeExtrusion width, the width of printed filaments, affects multiple critical aspects in mechanical properties in material extrusion additive manufacturing: filament geometry, interlayer load-bearing bonded area and fibre orientation for fibre-reinforced composites. However, this study aims to understand the effects of extrusion width on 3D printed composites, which has never been studied systematically.Design/methodology/approachFour polymers with and without short-fibre reinforcement were 3D printed into single-filament-wide specimens. Tensile properties, mechanical anisotropy and fracture mechanisms were evaluated along the direction of extruded filaments (F) and normal to the interlayer bond (Z). Extrusion width, nozzle temperature and layer height were studied separately via single-variable control. The extrusion width was controlled by adjusting polymer flow in the manufacturing procedure (gcode), where optimisation can be achieved with software/structure design as opposed to hardware.FindingsIncreasing extrusion width caused a transition from brittle to ductile fracture, and greatly reduced directional anisotropy for strength and ductility. For all short fibre composites, increasing width led to an increase in strain-at-break and decreased strength and stiffness in the F direction. In the Z direction, increasing width led to increased strength and strain-at-break, and stiffness decreased for less ductile materials but increased for more ductile materials.Originality/valueThe transformable fracture reveals the important role of extrusion width in processing-structure-property correlation. This study reveals a new direction for future research and industrial practice in controlling anisotropy in additive manufacturing. Increasing extrusion width may be the simplest way to reduce anisotropy while improving printing time and quality in additive manufacturing.

Influence of the Print Envelope Temperature on the Morphology and Tensile Properties of Thermoplastic Polyolefins Fabricated by Material Extrusion and Material Jetting Additive Manufacturing.

Additive manufacturing (AM) nowadays has become a supportive method of traditional manufacturing. In particular, the medical and healthcare industry can profit from these developments in terms of personalized design and batches ranging from one to five specimens overall. In terms of polymers, polyolefins are always an interesting topic due to their low prices, inert chemistry, and crystalline structure resulting in preferable mechanical properties. Their semi-crystalline nature has some advantages but are challenging for AM due to their shrinkage and warping, resulting in geometrical inaccuracies or even layer detaching during the process. To tackle these issues, process parameter optimization is vital, with one important parameter to be studied more in detail, the print envelope temperature. It is well known that higher print envelope temperatures lead to better layer adhesion overall, but this investigation focuses on the mechanical properties and resulting morphology of a semi-crystalline thermoplastic polyolefin. Further, two different AM technologies, namely material jetting (ARBURG plastic freeforming-APF) and filament-based material extrusion, were studied and compared in detail. It was shown that higher print envelope temperatures lead to more isotropic behavior based on an evenly distributed morphology but results in geometrical inaccuracies since the material is kept in a molten state during printing. This phenomenon especially could be seen in the stress and strain values at break at high elongations. Furthermore, a different crystal structure can be achieved by setting a specific temperature and printing time, also resulting in peak values of certain mechanical properties. In comparison, better results could be archived by the APF technology in terms of mechanical properties and homogeneous morphology. Nevertheless, real isotropic part behavior could not be managed which was shown by the specimen printed vertically. Hence, a sweet spot between geometrical and mechanical properties still has to be found.

Universal approach for developing reprocessable and reprintable plant oil-based resins for digital light processing 3D printing

Recently, researchers have shown great interest in the development of biobased and reprintable 3D printing materials for sustainable 3D printing. Herein, a method for developing plant oil (PO)-based digital light processing (DLP) printing resins that are both reprocessable and reprintable is proposed. Biobased UV-curable monomers (POPITs) containing dynamic hindered urea bonds (HUBs) from POs were synthesized via the thiol-ene click reaction. A range of DLP printing resins (POPIT-I) with high biobased content (52.6%–58.1%) were prepared by blending POPITs with the biobased dilute monomer isobornyl acrylate. These resins demonstrated good mechanical and thermal properties (e.g., tensile strength: 45.1–49.5 MPa and Tg: 74–92 °C), as well as high DLP printing quality. Reprocessable DLP printing was employed to fabricate large-volume parts through the dissociation and reorganization of HUBs, thereby reducing printing difficulty and printing time. Additionally, a powder blending and modification method was used to recycle and reprint printed materials. The printing materials, including printed green parts and discarded supporting materials, were milled into micron-sized powders and then blended with POPIT-I to prepare the powder blending resins. The milled powders in the powder blending resins were further modified by 2-(tert-butylamino) ethyl methacrylate to prepare reprinting resins. This process resulted in the grafting of C = C onto the powder surface, which eliminated heterogeneity between the powders and POPIT-I. The mechanical and thermal properties of the reprinting resins were comparable with those of POPIT-I even after three rounds of recycling. Furthermore, the reprinting method reported here is applicable to other dynamic covalent bond-based 3D printing systems.

Technical improvements in preparing 3D printed anatomical models for comminuted fracture preoperative planning

Preoperative planning of comminuted fracture repair using 3D printed anatomical models is enabling surgeons to visualize and simulate the fracture reduction processes before surgery. However, the preparation of such models can be challenging due to the complexity of certain fractures, particularly in preserving fine detail in bone fragments, maintaining the positioning of displaced fragments, and accurate positioning of multiple bones. This study described several key technical considerations for preparing 3D printed anatomical models for comminuted fracture preoperative planning. An optimized segmentation protocol was developed that preserves fine detail in bone fragments, resulting in a more accurate representation of the fracture. Additionally, struts were manually added to the digital model to maintain the positioning of displaced fragments after fabrication, reducing the likelihood of errors during printing or misrepresentation of fragment positioning. Magnets were also used to enable separation and visualization of accurate positioning of multiple bones, making it easier to visualize fracture components otherwise obscured by the anatomy. Finally, the infill for non-target structures was adjusted to minimize print time and material wastage. These technical optimizations improved the accuracy and efficiency of preparing 3D printed anatomical models for comminuted fracture preoperative planning, improving opportunities for surgeons to better plan surgical treatment in advance, reducing the likelihood of errors, with the goal of improving surgical outcomes.

Advancements in 3D-Printed Novel Nylon-6: A Taguchi Method for Surface Quality Sustainability and Mechanical Properties

This research aims to establish the ideal settings for Nylon-6 (PA6) three-dimensional printing utilizing the fused filament production process and examine the resultant surface roughness. ANOVA, S/N ratio, and modeling are explained, along with their application in identifying the ideal values for surface roughness, sustainability, and mechanical properties. Average-surface roughness (Ra), root-mean-squared surface roughness (Rq), print time (PT), print energy (PE), and tensile testing (T) were explored as response parameters to identify the impact of PA6 parameters (layer thickness, extrusion temperature, print speed, and infill density). Tests of validity demonstrated a significant decline in Ra, Rq, PE, PT, and T for the ideal values of the developed product of 10.58 µm and 13.3 µm, 23 min, 0.13 kWh, and 42.7 Mpa, respectively. Ra, Rq, PT, PE, and T have all been optimized using Taguchi techniques as a preliminary step towards application in future research and prototypes.