Help Of Additive Manufacturing Research Articles

Additive manufacturing from biomimetic approach

During the past millions of years since the beginning of our world, nature has created structures that are resistant to the various effects of the environment. However, these natural structures are quite complicated, so their production and artificial reproducibility with the tools of traditional manufacturing technology is a very difficult task. However, even complex structures can be produced relatively easily with the help of additive manufacturing. Using topological optimization techniques, lattice structure models with excellent mechanical characteristics can be created, which can be easily manufactured by exploiting the advantages of additive manufacturing. Applying natural structures (biomimetic approach) during topological optimization and produce the solution by additive manufacturing, light and high-strength structural alternatives can be created, any further structural analyses can be done.

Optimization of Cobalt Chrome 3D re-entrant Auxetics fabricated using Selective Laser Melting

An approach to study the effect of geometric parameters on the Poisson’s ratio of a three-dimensional re-entrant Cobalt Chrome Auxetic structure has been presented. The Auxetic mechanical structure has been realized with the help of Additive Manufacturing. The mechanical properties and Poisson’s ratio of the physical samples were determined using compression testing and Digital Image Correlation (DIC). A Finite Element model is used to estimate the Poisson’s ratio numerically. A Design of Experiments (DOE) and Finite Element Analysis (FEA) based optimization study is further performed in order to investigate the effects of the different geometric parameters on the Poisson’s ratio of the Auxetic samples. The DOE model is used to determine the values of the parameters for an optimal performance of the samples in terms of the observed Auxetic behaviour.

Significant Advancements in Numerical Simulation of Fatigue Behavior in Metal Additive Manufacturing-Review

The concept of “Industry 4.0” encourages the use of automated manufacturing processes and the use of advanced technological systems. Some of the most fundamental needs of the Fourth Industrial Revolution can only be met with the help of additive manufacturing. However, the mechanical behavior and reliability of additive-manufactured components are hardly recognized. This paper provides a systematic review of metal additive manufacturing technologies, materials, lattice structures, and fatigue properties as well as the development of numerical simulations. The current state of development in metal alloys and the optimization of cellular structures were presented. In addition, this paper discussed the main challenges in numerical simulation methods, their validation with experimental results, and the limitations of commercial software used. Overall, this paper provides an overview of metal additive manufacturing as well as a survey of its simulation software development to optimize several parameters in industrial and academic research fields. The results were critically analyzed and provided a benchmark for future research and development.

Wind Tunnel Testing and Validation of Helicopter Rotor Blades Using Additive Manufacturing

This research paper aims to validate the aerodynamic performance of rotor blades using additive manufacturing techniques. Wind tunnel testing is a technique used to find the flow characteristics of the body. Computational fluid dynamics (CFD) techniques are used for aerodynamic analysis, and validation should be done using wind tunnel testing. In the aerodynamic testing of models, additive manufacturing techniques help in validating the results by making models easily for wind tunnels. Recent developments in additive manufacturing help in the aerodynamic testing of models in wind tunnels. The CFD analysis of helicopter rotor blades was analyzed in this research, and validation was done using additive manufacturing techniques. Computational analysis was carried out for static analysis for the forward speeds of Mach numbers 0.3, 0.4, and 0.5. The results obtained were satisfactory to the previous results and were validated with wind tunnel testing. Results proved that the error percentage was lower, and the computational analysis was valid. In this research, models were designed using the FDM technique for wind tunnel testing as it is cost-effective and easy to manufacture.

Development of Phantoms for Multimodal Magnetic Resonance Imaging and Magnetic Particle Imaging.

Phantoms are crucial for the development of imaging techniques based on magnetic nanoparticles (MNP). They serve as test objects to simulate application scenarios but are also used for quality assurance and interlaboratory comparisons. Magnetic particle imaging (MPI) is excellent for specifically detecting magnetic nanoparticles (MNP) without any background signals. To obtain information about the surrounding soft tissue, MPI is often used in combination with magnetic resonance imaging (MRI). For such application scenarios, this poses a challenge for phantom fabrication, as they need to accommodate MNP as well as provide MR visibility. Recently, layer-by-layer fabrication of parts using Additive Manufacturing (AM) has emerged as a powerful tool for creating complex and patient-specific phantoms, but these are characterized by poor MR visibility of the AM material. We present the systematic screening of AM materials as candidates for multimodal MRI/MPI imaging. Of all investigated materials, silicone (Dreve, Biotec) exhibited the best properties with sufficient MR-signal performance and the lowest absorption of MNP at the interface of AM materials. With the help of AM and the selection of appropriate materials, we have been able to produce suitable MRI/MPI phantoms.

Experimental verification of a novel hierarchical lattice material with superior buckling strength

Recently, a systematic approach for the design of lattice materials with extreme buckling strength has led to optimized hierarchical lattice materials with unprecedented load carrying capacity. This is obtained at the cost of a small decrease in linear stiffness. However, the superior buckling resistance of such optimized hierarchical lattice materials has so far only been predicted numerically. In fact, concerns have been raised regarding the validity of the employed linear buckling analysis and potential risk of catastrophic failure due to the coalescence of multiple critical buckling modes. This work aims at refuting these concerns by designing and testing manufacturable novel hierarchical lattice materials with superior buckling strength. Thereby, the basis is provided for wide applications of these high-performing materials in mechanical design. A novel hierarchical material is generated for this work by combining the mentioned design procedure with a requirement on the minimum feature size to ensure manufacturability. For addressing the raised concerns, the optimized material design, together with a reference material, is realized with the help of additive manufacturing and experimentally tested in uniaxial compression. The obtained results are compared to numerical simulations considering geometrical and material nonlinearities, and an overall good agreement is found between experimental and numerical results. This confirms an increase in buckling resistance and post-buckling load carrying capacity by a factor of more than three compared to the regular reference lattice structure. Hence, the buckling superiority of this novel type of architected materials is clearly demonstrated.

A Study on Additive Manufacturing for Electromobility

Additive manufacturing (AM) offers the possibility to produce components in a resource-efficient and environmentally friendly way. AM can also be used to optimise the design of components in mechanical and physical terms. In this way, functionally integrated, lightweight, highly efficient, and innovative components can be manufactured with the help of additive manufacturing in terms of Industry 4.0. Furthermore, requirements in the automotive industry for drivetrain components are increasingly being trimmed in the direction of efficiency and environmental protection. Especially in electromobility, the topic of green efficiency is an essential component. Exhaust emission legislation and driving profiles for evaluating vehicles are becoming increasingly detailed. This offers the potential to apply the advantages of AM to vehicle types such as conventional, utility vehicles, and nonroad mobile machinery (NRMM), independent of the electrical drivetrain technology (hybrid or fully electrical). AM also allows for us to produce optimally adapted components to the respective requirements and use cases. In this review, the intersections of AM and electromobility are illuminated, showing which solutions and visions are already available for the different vehicle types on the market and which solutions are being scientifically researched. Furthermore, the potential and existing deficit of AM in the field of electromobility are shown. Lastly, new and innovative solutions are presented and classified according to their advantages and disadvantages.

Quasi-static compression performance of material extrusion enabled re-entrant diamond auxetic metamaterial: Fabrication, tuning the geometrical parameters and fibre reinforcements

Auxetics are the class of cellular structures which possess a negative Poisson’s ratio. Negative Poisson’s ratio is achieved through the careful design of the structures. Generally, auxetic structures are not feasible to manufacture using the conventional manufacturing processes due to the unit cell’s complex geometry, additive manufacturing help in alleviating this issue. Material extrusion/Fused Filament Fabrication (FFF) is the most simple, reliable, and low-cost additive manufacturing process in use. The mechanical performance of FFF processed auxetics is influenced by both geometrical parameters of auxetics and printing parameters. The careful selection of these parameters is of prime priority to avoid premature failure of printed structures. In the present work, the re-entrant diamond auxetic mechanical metamaterial is fabricated via FFF using the most commonly used FFF feedstock material, Acrylonitrile Butadiene Styrene (ABS). Initially, efforts are made to fine-tune the FFF process parameters to process these complicated geometrical structures. The ideal deformation parametric zone is defined with preliminary experiments to avoid premature failure of the re-entrant diamond structure. Experimental investigation of the effect of auxetic geometrical parameters and FFF process parameters on the quasi-static in-plane compressive performance is systematically evaluated using the design of experiments. The grey-based optimisation method is considered to optimise influential parameters for combined responses. Further, the re-entrant diamond auxetic metamaterial is reinforced with short carbon and glass fibre, and studied at optimal parametric levels. Reinforcements have enhanced the specific strength and stiffness of the structure with the loss of energy absorption characteristics. Microscopic studies confirm the predominant failure modes as a bond failure for CF-ABS and fibre breakage for GF-ABS. This study also aims to serve as fabrication guidelines to process complicated cellular composite structures via FFF.

Development of a topology‐optimized indoor crane trolley for additive manufacturing

AbstractWith the help of additive manufacturing, almost any geometry can be produced. Even those that are impossible or difficult to produce using conventional manufacturing techniques. Topology optimization offers the possibility of designing such geometries and thus also provides added technical value. Therefore, combining those two techniques allows the advantages of each field to be fully exploited. Using a practical example, the housing of a trolley of a smooth‐running crane system, this paper gives an idea of how the process can look like and what needs to be taken into account during implementation. Here it is shown that when considering a system with multiple interfaces to surrounding components, taking into account defined boundary conditions is not possible and a substitute model must be created, which requires a correction of the result.

Guiding bone formation using semi-onlay calcium phosphate implants in an ovine calvarial model.

The restoration of cranio‐maxillofacial deformities often requires complex reconstructive surgery in a challenging anatomical region, with abnormal soft tissue structures and bony deficits. In this proof‐of‐concept, the possibility of vertical bone augmentation was explored by suspending hemispherically shaped titanium‐reinforced porous calcium phosphate (CaP) implants (n = 12) over the frontal bone in a sheep model (n = 6). The animals were euthanized after week 13 and the specimens were subject to micro‐computed tomography (μCT) and comprehensive histological analysis. Histology showed that the space between implant and the recipient bone was filled with a higher percentage of newly formed bone (NFB) versus soft tissue with a median of 53% and 47%, respectively. Similar results were obtained from the μ‐CT analysis, with a median of 56% NFB and 44% soft tissue filling the void. Noteworthy, significantly higher bone‐implant contact was found for the CaP (78%, range 14%–94%) versus the Titanium (29%, range 0%–75%) portion of the implant exposed to the surrounding bone. The histological analysis indicates that the CaP replacement by bone is driven by macrophages over time, emphasized by material‐filled macrophages found in close vicinity to the CaP with only a small number of single osteoclasts found actively remodeling the NFB. This study shows that CaP based implants can be assembled with the help of additive manufacturing to guide vertical bone formation without decortification or administration of growth factors. Furthermore, it highlights the potential disadvantage of a seamless fit between the implant and the recipient's bone.

Bimetallic structure formation by Laser Powder Bed Fusion

Bimetallic structures are an excellent solution for a lot of engineering applications which require varying properties at different locations of the same object. Implementation of such structures into engineering fields can lead to easier maintenance, economical and space savings and can also open wider application possibilities. In recent years, production of bimetallic structures has been made possible with help of additive manufacturing (AM) technologies. Using laser powder-bed fusion AM, bimetallic structures can be created by depositing different materials in a layer-by layer fashion.In this work, two materials in powder form were used for bimetallic structure formation – CoCrMo and 17-4 PH stainless-steel. The bimetallic structure was successfully produced by using the L-PBF technology applied in EOSINT M280 machine. In-depth analysis of the 17-4 PH and CoCrMo materials and microstructural properties of the produced bimetallic sample were investigated in this study. A gradual change in chemical element distribution is observed at the two-material fusion zone. The thickness of the fusion zone is around 400-450 µm. The hardness of the fusion zone (104±2 HRB) is higher than the hardness of 17-4 PH (95±2 HRB) but lower than CoCrMo (111±2 HRB). The experimentally evaluated density of the bimetallic specimen is 8.01 g/cm3. The difference in values proves that the fusion zone of the specimen possesses unique characteristics that are not specific to either of the materials.

Fused Filament Fabrication (Three-Dimensional Printing) of Amorphous Magnesium Phosphate/Polylactic Acid Macroporous Biocomposite Scaffolds.

The ultimate goal of this paper is to develop novel ceramic-polymer-based biocomposite orthopedic scaffolds with the help of additive manufacturing. Specifically, we incorporate a bioceramic known as amorphous magnesium phosphate (AMP) into polylactic acid (PLA) with the help of the melt-blending technique. Magnesium phosphate (MgP) was chosen as the bioactive component as previous studies have confirmed its favorable biomaterial properties, especially in orthopedics. Special care was taken to develop constant diameter AMP-PLA composite filaments, which would serve as feedstock for a fused filament fabrication (FFF)-based three-dimensional (3D) printer. Before the filaments were used for FFF, a thorough set of characterization protocols comprising of phase analysis, microstructure evaluations, thermal analysis, rheological analysis, and in vitro degradation determinations was performed on the biocomposites. Scanning electron microscopy (SEM) results confirmed a homogenous dispersion of AMP particles in the PLA matrix. Rheological studies demonstrated good printability behavior of the AMP-PLA filaments. In vitro degradation studies indicated a faster degradation rate in the case of AMP-PLA filaments as compared to the single phase PLA filaments. Subsequently, the filaments were fed into an FFF setup, and tensile bars and design-specific macroporous AMP-PLA scaffolds were printed. The biocomposite exhibited favorable mechanical properties. Furthermore, in vitro cytocompatibility results revealed higher pre-osteoblast cell attachment and proliferation on AMP-PLA scaffolds as compared to single-phase PLA scaffolds. Altogether, this study provides a proof of concept that design-specific bioactive AMP-PLA biocomposite scaffolds fabricated by FFF can be potential candidates as medical implants in orthopedics.

Introduction to 3D printing: techniques, materials and agricultural applications

The Production of complex products is easily possible with the help of additive manufacturing. By using additive manufacturing products may be mass-produced. Compared to traditional subtractive manufacturing, Additive manufacturing is advantageous in short design cycles, suitable for manufacturing complex structures, and high material utilization. Polymers and composites are frequently used in AM technologies, which have evolved into a variety of industrial and emerging applications. Among the many materials currently used in 3D printing are ceramics, metals, polymers, and concrete. ABS and PLA thermoplastics are the most often used materials for agricultural 3D printing since they are easy to print and relatively cheap. This article provides an overview of 3D printing technologies, materials, and applications in agriculture.

Digital light processing strength-strong ultra-thin bioceramic scaffolds for challengeable orbital bone regeneration and repair in Situ

The orbital fracture regeneration and reconstruction is still a catastrophic challenge due to the extremely thin anatomical structure and different defect shapes in various clinical conditions. The conventional biomaterials and preparation technique are often inefficient in satisfying porous scaffold architecture designs with respect to their required structural stability and biological performances. Here we developed the ultrathin scaffolds with high- precision pore structure and appreciable osteogenic activity for orbital bone repair via digital light processing (DLP) stereolithography. The dilute magnesium-substituting wollastonite (CSi-Mg) bioceramic scaffolds of ~1.5 mm in thickness and over 60% in porosity were investigated systematically, and compared with another calcium-magnesium silicate (i.e. akermanite) and the pure wollastonite porous counterparts. The results showed that the flexural strengths (~6−22 MPa) and in vitro biodegradation of such bioceramic scaffolds could be tuned during their chemical composition (i.e. Mg content) design stage, and the CSi-Mg scaffolds were also beneficial for osteogenic cell activity in vitro. In particular, the CSi-Mg scaffolds could readily enhance the new bone ingrowth at 4 weeks of implantation in a critical-sized rabbit orbital bone defect model, and such strength-strong scaffolds exhibited outstanding orbital defect repair efficacy after 12 weeks of implantation, in comparison with the structural instability of other scaffolds. Basically, it is demonstrated that the dilute magnesium doping in wollastonite bioceramic can be favorable for developing the mechanically reliable scaffolds with high porosity and bioactivity but quite thin wall morphology, and meanwhile the DLP-assisted additive manufacturing help us to optimize such porous bioceramic design with respect to their required structural stability for orbital bone reconstruction.

Urgent need hybrid production - what COVID-19 can teach us about dislocated production through 3d-printing and the maker scene

BackgroundThe COVID-19 pandemic has led to large-scale shutdowns in society. This resulted in global supply bottlenecks for medical protective equipment. The so-called Maker Movement recognized this emerging problem early on and, with the help of additive manufacturing (AM), began developing and manufacturing half masks or face shields as personal protective equipment (PPE). This knowledge has been made available in many places in form of open source product data, so that products could be adapted and improved, saving development time.MethodsThis production and innovation potential has been taken up and professionalized by the authors of this article. By means of a proof-of-principle we provide an overview of the possibility and successful unique introduction of a so-called professional “hybrid production” in a micro factory using 3D-printing at the place of greatest demand in a hospital by medical personnel to produce their own PPE. Furthermore the learning process and future benefits of on site 3D-printing are described.ResultsOur proof-of-principle successfully showed that the allocation of 3D-printing capabilities in the hospital infrastructure is possible. With assistance of the engineers, responsible for product design and development, the medical staff was able to produce PPE by means of AM. However, due to legal uncertainties and high material and production costs the usability is severely limited.ConclusionsThe practical research showed that a complete implementation of the concept and the short-term establishment of a 3D-printing factory for the autonomous supply of a hospital with PPE was not feasible without further efforts. Nevertheless, it has enabled the medical staff to use AM technologies for future research approaches.

In-Situ Lithium-Ion Batteries Thermal Runaway Detection and Overcharge Performance Analysis with Internal Resistance Temperature Detector

Thermal safety is the main roadblock for applications of high energy density lithium-ion batteries (LIBs) and catastrophic LIB failure has long been a public concern. There have been numerous LIB safety testing standards and many LIB safety management devices, including isolating shutdown separators, protective electrode coatings, safety valve, etc., that are proposed for LIB service safety and reliability improvement. Despite the application of LIB tests and safety devices, thermal runaway is still reported as a major threat to equipment and personal safety. In order to improve the in-service safety, the battery management system (BMS) and safety devices need to examine and analyze the LIB performance in a real-time manner so the rapid thermal runaway progress can be detected and prevented at an early stage. Due to the complex nature and rapid reaction rate of thermal runaway, BMS and safety device with capability of comprehensive in-situ analysis of LIB thermal runaway progress have seldomly been reported. A simple BMS capable of examining the LIB thermal safety and detecting thermal runaway related reactions needs to be developed.Existing LIB thermal safety management systems typically rely on temperature sensors including thermocouples, thermistors, fiber bragg-grating sensors, etc. Despite their success in LIB surface temperature measurement, they cannot be applied for direct electrode temperature measurement, which is crucial for thermal runaway detection and prevention. Existence of thermal resistance between the battery surface and electrodes also impedes the development of quick responding LIB temperature monitoring systems based on surface temperature measurements. To address this issue, we propose the application of resistance temperature detectors (RTDs) in LIBs with the help of additive manufacturing. By embedding RTDs into operating LIBs, reliable in-situ monitoring of the electrode temperature can be achieved, which is beneficial for early detection and prevention of thermal runaway. In this work, thermal runaway in LIBs was triggered by overcharge and external short circuit (ESC). Battery temperature was recorded by the internal RTD embedded on the electrodes and external RTD mounted on the battery surface. Significant temperature difference of ~9 ºC and ~20 ºC were detected between the electrode and battery surface in ESC and overcharge of small lab-fabricated Li-ion coin cells. The temperature difference can be as high as ~200 ºC for large capacity Li-ion pouch cells. In ESC, the internal RTD detected thermal runaway ~ 10 times faster than the external RTD despite of the battery type. Besides, the internal RTDs can provide accurate electrode temperature contour and comparison of anode and cathode temperatures during regular operation and thermal runaway of LIBs. The solid electrolyte interface (SEI) which is comprised of reduced electrolytic compounds like ROCO2Li, (CH2OCO2Li)2 and ROLi, can contribute to heat generation in LIB thermal runaway. The effect of SEI can be analyzed with in-situ examination of cathode and anode temperatures. Transient temperature difference captured by the internal RTD indicated that anode is the critical electrode and contributes more to the heat generated in thermal runaway. This helps to optimize temperature sensor arrangement for more effective monitoring and prevention of thermal runaway.The internal RTD also provides opportunity for in-situ analysis of chemical reactions in thermal runaway. Gas generated in thermal runaway has a high concentration of CO, H2, CH4, etc., which is prone to ignition and explosion. The generated gas can affect LIB structure as it causes deformation of electrodes and separators. Although this is hard to be detected with most basic BMS, it can be examined with electrode and battery surface temperature comparison, as the LIB thermal resistance is changed during gas accumulation. Different modes of thermal runaway can be differentiated by analyzing the temperature profiles, which allows for customized thermal runaway prevention and control strategy.

АДИТИВНІ ТЕХНОЛОГІЇ: ВИКОРИСТАННЯ АЛЬТЕРНАТИВНИХ МАТЕРІАЛІВ В ДИЗАЙНІ ТА МИСТЕЦТВІ

Collaboration between art and sciencebrings into beinga new way of project making that involves CAD (Computer-aided design) with its following upcoming producing with Additive manufacturing technologies. This approach of production is characterized  with high level of efficiency of resources usage that involves collaboration of the human and the computer for modeling and coding properties of upcoming product with the most effective indications. Awareness of potential of innovative technologies provides advantages in different spheres, including art and design. Different ambitious projects that require advanced technologies are developed with the help of additive manufacturing. Rapid breaks out of AM expands and improves techniques of manufacturing products of different scale and alternative materials to operate with. Taking into consideration current ecological situation in the world an important place takes material ecology subject and alternative techniques of additive fabrication. The research shows contemporary world breakthroughs in ecological materials development and its usage in product design in different fields. Furthermore, there is an overview of a case that in which biological active material is involved into 3D-manufacturing. Considering the research the emphasis is put at renewable materials involving techniques of 3D-production as well as sustainable methods of fabrication and their place in design of 21 century. In addition, it is showed a case of environmentally friendly additive manufacturing in Ukraine. Equally important to mention the perspective of developing additive manufacturing in Ukraine owning to a high potential of intellectual resources. Keywords: additive manufacturing, 3D printing, design, alternative materials, ecological materials.

Additively manufactured trapezoidal grooves for wideband and high gain Ku‐band antenna

Grooves around aperture antennas are known to be instrumental in obtaining directive antenna patterns. The shapes of the grooves are often restricted to rectangular or triangular due to manufacturing difficulties in traditional metal machining, and because of this reason, the effect of groove shape on antenna performance is often overlooked. The aim of this study is to analyze different groove shapes with the help of additive manufacturing. Waveguide slot fed, dual cavity aperture antenna with grooves is designed and the effect of groove shapes on antenna performance is studied at Ku band. Two antennas with and without grooves are built using 3D printing technology. Measured antenna performance reveals 5 GHz bandwidth covering 10 to 15 GHz for Ku-band satellite communications and part of the X-band applications. Proposed antenna achieves 13.25 dBi peak gain at 14 GHz and the gain is better than 11.25 dBi over the entire Ku-band uplink and downlink frequency bands.

Experimental validation of additively manufactured optimized shapes for passive cooling

This article confirms the superior performance of topology optimized heat sinks compared to lattice designs and suggests simpler manufacturable pin-fin design interpretations. The development is driven by the wide adoption of light-emitting-diode (LED) lamps for industrial and residential lighting. Even for advanced lighting technology as LEDs, a large fraction of the input power is still converted to heat. Thus, efficient thermal control lowers energy waste, increases lifetime and reduces maintenance costs of this rapidly growing, expectedly soon to be governing, illumination technology. The presented heat sink solutions are generated by topology optimization, a computational morphogenesis approach with ultimate design freedom, relying on high-performance computing and simulation. Optimized devices exhibit complex and organic-looking topologies which are realized with the help of additive manufacturing. To reduce manufacturing cost, a simplified interpretation of the optimized design is produced and validated as well. Numerical and experimental results agree well and indicate that the obtained designs outperform lattice geometries by more than 21%, resulting in a doubling of life expectancy and 50% decrease in operational cost.

Training Young Maxillofacial Surgeons or Trainees Using Additive Manufacturing

Cranio-maxillofacial surgery requires high precision to obtain the desired results. However, to perform such surgeries a surgeon has to go-through intense training. Earlier surgeon was solely dependent on the data obtained from conventional X-ray films which would give only the 2 dimensional depictions. There existed a need for a depiction of the third dimension. The virtual models were obtained by 3 d Scans but the real time performing surgery was the next step. The virtual imaging can be made physical with help of additive manufacturing (AM). AM or 3D-printed models to train new surgeons before they perform complex surgery resolves a dire need for proper training and practice. Additive manufacturing is the perfect technique to create hyper realistic training replicas of complex or rare pathologies which gives a life like feel over which a trainee can practice the art of surgery without the risk of losing an actual patient. The opportunity to use 3D Printing technology in hospitals creates a valuable learning opportunity for new surgeons. The 3D CT images are converted into lifelike, soft, 3D-printed models which can be cut, sewn and operated on. This is just a much more rapid way of expanding the circle of competence of budding surgeons. Apart from regular training, 3D-printed models can also be used in trial runs before an actual surgery is performed.