3D Printer Nozzle Research Articles

Development of a flat jet delivery system for soft X-ray spectroscopy at MAX IV.

One of the most challenging aspects of X-ray research is the delivery of liquid sample flows into the soft X-ray beam. Currently, cylindrical microjets are the most commonly used sample injection systems for soft X-ray liquid spectroscopy. However, they suffer from several drawbacks, such as complicated geometry due to their curved surface. In this study, we propose a novel 3D-printed nozzle design by introducing microscopic flat sheet jets that provide micrometre-thick liquid sheets with high stability, intending to make this technology more widely available to users. Our research is a collaboration between the EuXFEL and MAX IV research facilities. This collaboration aims to develop and refine a 3D-printed flat sheet nozzle design and a versatile jetting platform that is compatible with multiple endstations and measurement techniques. Our flat sheet jet platform improves the stability of the jet and increases its surface area, enabling more precise scanning and differential measurements in X-ray absorption, scattering, and imaging applications. Here, we demonstrate the performance of this new arrangement for a flat sheet jet setup with X-ray photoelectron spectroscopy, photoelectron angular distribution, and soft X-ray absorption spectroscopy experiments performed at the photoemission endstation of the FlexPES beamline at MAX IV Laboratory in Lund, Sweden.

Orientation of Liquid Crystalline Polymers after Filament Extrusion and after Passing through a 3D Printer Nozzle

Orientation of Liquid Crystalline Polymers after Filament Extrusion and after Passing through a 3D Printer Nozzle

3D Printer Nozzle Structure Form Optimal Structural Analysis

The most representative technology of 3D printing is fused deposition modeling (FDM). To improve the printing accuracy of FDM technology, this paper first takes the outlet diameter, angle of convergence, and rectifier section length of the nozzle as the influencing factors. It takes the melt outlet speed stability, viscosity, and outlet pressure as the indexes to design the orthogonal test. Then, COMSOL Multiphysics fluid–solid coupling simulation was used to simulate and analyze the structural characteristics of the 3D printer nozzle, and the range analysis method was used to analyze the data. Finally, the two-phase flow combination was used to simulate the morphological characteristics of the melt flowing out of the nozzle. The results show that the simulation results of the two materials are similar. As the nozzle diameter decreases, the melt pressure decreases, the velocity increases, and the viscosity decreases. For PLA wire rods, the optimal structure of the nozzle is that the outlet diameter is 0.2 mm, the rectifier section length is 1.5 mm, and the angle of convergence is 60°. For ABS wire, the optimum structure of the nozzle is that the outlet diameter is 0.2 mm, the rectifier section length is 1.5 mm, and the angle of convergence is 30°. The nozzle outlet diameter is inversely proportional to the printing accuracy for ABS and PLA materials. The research results provide a theoretical reference for optimizing the nozzle structure for 3D printing.

CO2 Capture with Polyethylenimine Supported on 3D-Printed Porous SiO2 Structures.

Amines supported on porous solid materials have a high CO2 adsorption capacity and low regeneration temperature. However, the high amine load on such substrates and the substrate itself may lead to substantial pressure drop across the reactor. Herein, we compare the CO2 adsorption capacity and pressure drop of fumed silica powder to 3D-printed monolithic fumed silica structures, both functionalized by polyethylenimine (PEI), and find a drastically reduced pressure drop for 3D-printed substrates (0.01 bar vs. 0.76 bar) in the sorption bed with equal CO2 adsorption capacity. Furthermore, the effect of 3D-printing nozzle diameter and PEI loading on the adsorption capacity are investigated and the highest capacities (2.0 mmol/g at 25 °C with 5000 ppm CO2) are achieved with 0.4 mm nozzle size and 34 wt% PEI loading. These high capacities are achieved since the 3D printing and subsequent sintering (700 °C) of monolithic samples does not compromise the surface area of the fumed silica. Finally, the comparison between 3D-printed monoliths and extruded granulate of varying diameter reveals that the ordered channel system of 3D-printed structures is superior to randomly oriented granulate in terms of CO2 adsorption capacity.

Inline CT-Analysis of the Melting Area during Fused Filament Fabrication

In the 21st century, 3D printing has become a mainstream process for prototyping and low-volume production. Fused Filament Fabrication is the most commonly used process for 3D printing plastics. A plastic filament is melted in a nozzle and a component is built up layer by layer. As with all manufacturing processes, there is an interest in continuously optimizing and improving the FFF process. One approach is based on process simulation, which provides a better understanding of the process. Subsequently, it is always necessary to validate the simulation models with the real process. This validation has only been possible to a limited extent in the case of FFF. In this work, a method is presented that allows a non-destructive investigation of the melt behaviour during the printing process. For this purpose, a 3D printer nozzle with an extruder was integrated into an X-ray computed tomography system. Thus, a computed tomography scan can be performed during the extrusion process. By using highly absorbent tungsten filaments, sufficient contrast can be created between the metal nozzle and the plastic filament to allow analysis of the melt behaviour. This setup makes it possible to distinguish between the solid filament area and the melt area, as well as to determine the contact between the filament and the die wall. In doing so, simulations can be validated and nozzle geometries can be improved.

The process‐structure–property relationship of 3D printed G‐Polymer using fused filament fabrication technique

AbstractThe ever‐increasing demand for additive manufacturing (AM) is driven by the technology's rapid prototyping and flexible manufacturing benefits. Among the various AM techniques, fused filament fabrication (FFF) is one of the most commonly used techniques, in which thermoplastic polymer filaments are deposited layer by layer to create the final part. This technique has been used extensively in various sectors. However, new materials have yet to be developed for use in FFF. This research aims to introduce a new biodegradable highly amorphous polyvinyl alcohol (HAVOH), commercially known as G‐Polymer (GP), into the scope of FFF, to propose a process window for the fabrication of parts with enhanced mechanical properties and to discover the process‐structure–property relationship for this material. This study investigates the effect of five key parameters in GP FFF, including raster angle, number of contours, nozzle temperature, build platform temperature, and print speed. The results of the chemical, thermal, and thermo‐mechanical analysis of the filaments before and after hot extrusion of the 3D printer nozzle showed a significant increase in the mechanical properties of the hot‐extruded filaments. In addition, the mechanical characterization of 3D printed parts showed that increasing the number of contours can improve the mechanical properties of parts, while the raster angle can have a complex effect. The mechanical properties of the parts are also improved by reducing the temperature of the nozzle and the build platform. Printing speed, as an essential parameter in AM, was related to the previously mentioned parameters, and the results showed that increasing the printing speed could improve the UTS and Young's modulus of the 3D printed part.Highlights A novel biodegradable polymer (HAVOH) was introduced into the scope of FFF. The hot extruded G‐Polymer filament from the nozzle showed improved mechanical properties. 180°C nozzle and room temperature platform resulted in improved mechanical properties. 3D printed parts with +45°/−45° raster angle show improved mechanical properties 110 mm/s print speed results in higher mechanical strength than 70 mm/s print speed.

Development and Outlook for the FDM Printed Nozzle Structure

Abstract:: The nozzle is one of the parts of a 3D printer that cannot be missed because of its widespread popularity in recent years. The nozzle's structure determines the quality of the printed product; therefore, selecting a suitable nozzle structure is crucial. With the advancement of 3D printing technology in recent years, 3D printers have progressively come under investigation. Examining the design of the nozzle, feeding mechanism, and printing platform can help to increase the quality of the prints. The design and enhancement of the nozzle structure are beneficial to the advancement of 3D printing technology since it is one of the key elements influencing print quality. Using the research methods, research content, and invention structure of the most recent representative patents on this nozzle structure, the features and operating principle of the 3D printed nozzle structure are illustrated. To classify and examine the nozzle temperature and nozzle clogging that impact the nozzles, a patent analysis of various types of 3D printing nozzle structures is carried out. Future trends in 3D printing nozzle structures are also covered. The issues caused by nozzle work can be resolved to increase product quality and precision by comparing various 3D printing nozzle structures. This will also lead to the invention of more relevant patents in the future, including those about printing numerous nozzles and high-strength metals.

Upscaling active rheology control to cement mortar with the intervention of an inline magnetic field

Upscaling the printing ink from cement paste to mortar level is the path people must take to apply active rheology control to smart and advanced digital fabrication, which will decrease the content of binder and reduce carbon footprint. This study investigates the rheological response of cement mortars with carbonyl iron particles (CIPs) by using penetration tests and vane tests. A customized magnetorheological test setup, making use of a pipe/nozzle-like inline magnetic intervention, was developed to modify the rheological properties of responsive mortars within a few seconds. The alignment of magneto-responsive particles and the hindrance of sand on magneto-responsive particles in the mortars were visualized and determined by scanning electron microscopy (SEM). With an inline magnetic field, the yield stress determined by the slow penetration test and the torque measured by the vane test increased by a significant factor. The magneto-responsive effect and the response speed rate of the mortar can be adjusted on demand and in time. The effect of cement-to-sand (c/s) ratios and sand gradations on the magnetorheological response of cement mortars was studied. With the increase of sand content (decrease of c/s ratio), the percent increase of yield stress and torque decreased and the magneto-response speed reduced, which indicates a reduction in response efficiency. The magneto-responsive particles could more easily move in the mortar when the particle size of sand increased. Experimental proofs of concept to apply active rheology control to a 3D printing nozzle or pumping line were conducted.

Impact behaviour of 3D printed fiber reinforced cementitious composite beams

Recent interest has grown in using 3D printing for military and civil defense engineering, particularly for infrastructure resilience against impacts. This study delves into the impact resistance of 3D printed fiber-reinforced cementitious composite (FRCC) beams. By analyzing varying fiber content, impact directions, and 3D printing nozzle sizes, the research found that the total energy dissipation of 3D printed FRCC beams was more than 40% higher and the 3D printed beams exhibited superior impact resistance compared to traditional beams, largely due to the fibers' role. The impact energy dissipation varied with different impact directions for the specimens, and the Z direction was identified as the most resistant, demonstrating anisotropic behavior in impact resistance. Smaller nozzle sizes in printing showed higher total energy dissipation, indicating increased impact resistance. X-ray analysis further revealed that the 3D printing process creates denser beams with better fiber–matrix adhesion and less porosity, improving overall impact resistance.

Effect of Collector Rotational Speed on the Morphology and Structure of Solution Blow Spun Polylactic Acid (PLA).

Apart from structure and composition, morphology plays a significant role in influencing the performance of materials in terms of both bulk and surface behavior. In this work, polylactic acid (PLA) constituted by submicrometric fibers is prepared. Using a modified electrospinning (ES) device to carry out solution blow spinning (SBS), the fibrillar morphology is modified, with the aim to induce variations in the properties of the material. The modification of the ES device consists of the incorporation of a source of pressurized gas (air) and a 3D-printed nozzle of our own design. For this work, the morphology of the PLA submicrometric fibers is modified by varying the rotational speed of the collector in order to understand its influence on different properties and, consequently, on the performance of the material. The rotational speed of a cylindrical collector (250, 500, 1000 and 2000 rpm) is considered as variable for changing the morphology. Morphological study of the materials was performed using scanning electron microscopy and image analysis carried out with ImageJ 1.54f software. Besides a morphology study, structural characterization by Fourier transformed infrared spectroscopy using attenuated total reflectance of prepared materials is carried out. Finally, the morphology and structure of produced PLA fibrous mats were correlated with the analysis of mechanical properties, wettability behavior and adhesion of DH5-α E. coli bacteria. It is of interest to highlight how small morphological and chemical structure variations can lead to important changes in materials' performance. These changes include, for example, those above 30% in some mechanical parameters and clear variations in bacterial adhesion capacity.

A Multi-criteria decision making approach for 3D printer nozzle material selection

Rapid advancements in 3D printing technology have compelled the manufacturers to search for better nozzle material in the extruder of 3D printers. Materials ranging from brass to tungsten carbide and ruby are primarily used as the nozzle material. In 3D printing technology, due to major constraints imposed by the filament material and other decisive factors, no single nozzle material satisfies all the desired characteristics for a real time application. Thus, it has become crucial to select the most appropriate nozzle material with the desired properties for enhanced 3D printing performance. In this paper, the performance of eight candidate nozzle materials is evaluated based on nine selection criteria. Entropy method is utilized to determine the criteria weights, whereas, evaluation based on distance from average solution (EDAS) method is employed to identify the best suited 3D printer nozzle material. Tungsten carbide emerges out as the best choice, followed by titanium alloy (TiAl6V4). This paper also proposes a sensitivity analysis to establish the robustness of the adopted methodology.

Design of Viscosity and Nozzle Path Using Food 3D Printer and Pneumatic Pressure Syringe-Type Dispensing System

Recent advancements in 3D printing technology have integrated with Fourth Industrial Revolution technologies such as robotics and artificial intelligence, aiming to overcome the limitations of conventional manufacturing methods. In the field of functional foods, solvent casting, a common manufacturing technique, has been adopted to produce film-like structures with desired sizes and uniform thickness. However, the typical method of coating or injection on a conventional continuous film is difficult to produce in small amounts. To address this limitation, in the study, we developed a pneumatic pressure syringe-type dispensing system integrated with a food 3D printer utilizing fused deposition modeling (FDM) technology. A syringe type is needed to discharge crude liquid manufactured in the food field in a hygienic environment, and a 3D printing method that is easy to manufacture in small quantities or on demand was utilized. Through simulation and experiment, we wanted to confirm whether stable ejection results are generated according to the selected nozzle-based viscosity, inflow conditions, and the nozzle movement path of the food 3D printer. Based on the nozzle selected through simulation, it was confirmed that the fluid and flow velocity distribution of the viscous material were uniformly distributed and discharged under the conditions of 30,000 cps and inflow rate. By setting the parameters of the food 3D printer and preparing a coenzyme Q10 (CoQ10) sample, we achieved a stable oral dissolving film (ODF) extrusion shape through the design of viscosity and 3D printer nozzle path. The optimal viscosity range for the ODF solution was found to be 25,000 to 35,000 cps, exhibiting precise dimensions and shapes without distortion and yielding the most stable extrusion results. We defined four different nozzle path designs based on minimizing the movement of the 3D printer nozzle. Among them, a 16-step path design demonstrated a stable extrusion method, showing no tailing phenomenon under the conditions of 0.2 MPa pressure and −15.4 KPa vacuum pressure. In future research, we plan to conduct additional research to determine whether the discharge results vary depending on conditions such as viscosity of the crude liquid, nozzle path combination, and ODF thickness.

Molding quality control with nonlinear forming method in 3D cement printing

3D cement printing is an emerging technology that can construct building elements without formwork, which has broad application prospects in the field of constructing non-linear and complex building structures. However, the high-quality printing and molding of nonlinear structure has become one of the bottleneck technologies restricting the development of 3D building printing. In this paper, variable radian 3D printing nozzle is firstly developed to verify the controllability of extruded concrete material based on self-developed 3D building printer. Then, variable radian forming theory is presented and used to evaluate the mechanism material fracture and accumulation, and improve the molding quality of nonlinear structure. Finally, simulation analysis and experiments are designed to explore the controllable mechanism of variable radian molding and verify the consistency between the experimental results and the theoretical analysis. The research results can promote the application of 3D printing in the construction industry, and provide support for the utilization of building resources and green buildings.

Direct‐Ink‐Written Cholesteric Liquid Crystal Elastomer with Programmable Mechanochromic Response

AbstractCholesteric liquid crystal elastomers (CLCEs) are unique anisotropic rubbers that can change their structural color in response to various stimuli such as heat, chemicals, electric fields, and mechanical stress. Methods such as anisotropic deswelling and surface alignment have been adopted to prepare CLCEs; however, they have limitations in creating spatially controlled CLCE geometries. In this work, a direct ink writing (DIW)‐based 3D‐printable CLCE that can be prepared by extruding viscous CLC ink is developed through a 3D printer nozzle, followed by photopolymerization. Interestingly, the helical axis is inclined to the printing direction by ≈32° due to a combination of the shear‐induced alignment causes during extrusion and the elongational force generated during deposition onto the substrate. This unusual helical axis distortion leads to both blue and red shifts of the reflection color depending on the direction of observation relative to the printing axis. Notably, the printed CLCE exhibits anisotropic mechanochromism upon stretching, because of the stretching‐direction‐dependent variations in the slant angle of the helical axis. This anisotropic mechanochromism can be harnessed to develop a unique CLCE‐based strain sensor displaying intricate color patterns upon stretching, with significant application potential in encryption, anticounterfeiting, and structural health monitoring.

Design, manufacturing, evaluation, and performance of a 3D-printed, custom-made nozzle for laser wakefield acceleration experiments.

Laser WakeField Acceleration (LWFA) is extensively used as a high-energy electron source, with electrons achieving energies up to the GeV level. The produced electron beam characteristics depend strongly on the gas density profile. When the gaseous target is a gas jet, the gas density profile is affected by parameters, such as the nozzle geometry, the gas used, and the backing pressure applied to the gas valve. An electron source based on the LWFA mechanism has recently been developed at the Institute of Plasma Physics and Lasers. To improve controllability over the electron source, we developed a set of 3D-printed nozzles suitable for creating different gas density profiles according to the experimental necessities. Here, we present a study of the design, manufacturing, evaluation, and performance of a 3D-printed nozzle intended for LWFA experiments.

3D-printed triaxial nozzles fabricated by stereolithography to prevent backflow in soft matter biofabrication

Three-dimensional (3D) bioprinting has a significant influence on tissue engineering by virtue of its capacity to produce complicated structures with complex geometries that are challenging to recreate using conventional manufacturing methods. However, the nozzle design and fabrication remain a limitation within extrusion-based 3D bioprinting, restricting and compromising the overall potential of this technology. The proposed nozzle design combines three Luer-Lok compatible inlets and an outlet within the printed body, eliminating manual assembly and enhancing fabrication consistency and quality. Furthermore, a finite element analysis of the fluid flow in the nozzle demonstrated the effectiveness of the nozzle to minimize backflow, in comparison with a traditional nozzle design. The tetrameric IIZK (Ac-Ile-IIe-Cha-Lys-NH2) and IIFK (Ac-Ile-IIe-Phe-Lys-NH2) peptide bioinks were used to 3D-print a variety of 3D scaffolds of varying complexity, with good resolution and gel continuity. Our work successfully demonstrated the fabrication of a novel design and its potential, and by means of 3D bioprinting, we assessed the biocompatibility and cell viability of the cell-laden constructs. This study highlights the capability of the novel design, which aids the field of tissue engineering, allowing 3D extrusion-based bioprinting to be utilized in the production of cell-incorporated constructions or scaffolds.

Optimizing rheological properties for printability: low-temperature extrusion 3D printing of hydroxyapatite-polycaprolactone mixture inks for bone tissue engineering

Introduction: Low-temperature extrusion three-dimensional printing (LTE-3DP) using viscous ceramic-polymer inks has shown promise for bone tissue engineering. This process involves formulating a flowable ink by combining ceramic powders and other components with organic or inorganic polymer solutions, which can then be extruded through a 3D printer nozzle. LTE-3DP allows the incorporation of high fractions of bioactive ceramics and thermally labile additives such as drugs, proteins, and biomolecules into the inks to promote osteogenesis and bone regeneration. The rheology of the ink, influenced by various variables, significantly impacts the printability and form fidelity of the resulting scaffolds. These variables include the composition of the polymer solution and the size and weight ratio of ceramic microparticles. In this study, we posited that the printability of hydroxyapatite (HA) and polycaprolactone (PCL) mixture inks could be optimized by tailoring their rheological properties.Methods: We conducted a systematic investigation, varying the PCL weight percentage and HA:PCL weight ratio, to examine the effects of the ink’s composition on its viscosity and storage modulus, as well as its printability and the mechanical properties of 3D printed HA:PCL scaffolds.Results: We demonstrated that HA:PCL inks exhibit predictable non-Newtonian fluid behavior at higher fractions of HA, displaying significant shear thinning at elevated shear rates, which can facilitate extrusion through a 3D printing nozzle. We identified printable ink compositions based on filament continuity and scaffold form fidelity criteria. Moreover, we performed computational simulations to analyze the ink flow through an extrusion nozzle. These simulations utilized the Herschel-Bulkley-Papanastasiou constitutive model, considering the rheological properties obtained from experimental measurements. By combining experimental measurements and computational simulations, we formulated a non-dimensional Printability number that predicts whether an ink is printable based on the ink’s rheological parameters and printer-specific factors. Furthermore, we evaluated the compressive properties of printed HA:PCL scaffolds and characterized the effects of PCL% and HA:PCL ratio on the hyperelasticity observed in response to compressive deformations.Discussion: This hybrid approach using experimental rheology and FE simulations provides a framework to define the printability of ceramic-polymer ink formulations, which could help streamline the 3D printing of novel inks for bone tissue engineering.

Multi-Material 3D-Printing Nozzle Design Based on the Theory of Inventive Problem Solving and Knowledge Graph

Fused deposition modeling (FDM) technology is an emerging technology with promising applications, with the nozzle playing a crucial role in extrusion, heating, and material ejection. However, most current extrusion-based 3D printers handle only single-material printing, making the integration of multiple materials through a single nozzle challenging due to compromised quality and clogging risks. This paper introduces a method to design multi-material 3D printing nozzles using the Theory of Inventive Problem Solving (TRIZ) and knowledge graph (KG). By optimizing design and leveraging TRIZ’s contradiction resolution principle, this study addressed bottlenecks and complexities in multi-material nozzle design, providing insightful recommendations. A patent knowledge graph focused on spray nozzles was created, storing material properties, design elements, and constraints for enhanced knowledge sharing. Building on identified challenges and recommendations, the study utilized keyword searches and associative paths in the knowledge graph to guide designers in generating innovative solutions. Validation was achieved through two distinct nozzle design models resulting from guided innovations. The TRIZ-KG methodology presented in this paper provides designers with a systematic cognitive framework to empower designers in overcoming technical obstacles and proposing precise solutions.

CT-Analysis of the Melting Area in the Fused Filament Fabrication Process

3D printing has established itself in the 21st century as the process for producing prototypes and very small series. In the plastics sector, the fused filament fabrication (FFF) process is used in particular. A plastic filament is melted in a nozzle and a component is built up layer by layer. As with all manufacturing processes, there is an interest in continuously optimizing and improving the FFF process. One possibility is based on process simulations, which enable a better understanding of the entire process. Afterwards a validation of the simulation with the real process is always necessary. In the case of FFF, this validation was so far only possible to a limited extent. In this work, a method is presented that enables a non-destructive investigation of the melting behavior during the printing process. For this purpose, a 3D printer nozzle with an extruder was integrated into an X-ray computed tomography system. Thus, a computed tomography scan (CT scan) can be performed during the extrusion process. By using filaments with high absorbent tungsten, a sufficient contrast can be created between the metal nozzle and the plastic filament, which allows an analysis of the melting behavior. This setup allows to distinguish between the solid filament area and the melt area, as well as to determine contact between the filament and the nozzle wall. In this way, the simulations can be validated and nozzle geometries to be improved in the future by means of improved simulation tools.

Synchronized 3D Printing and Corona Charging for One-Step Prototyping of Polarized Polylactic Acid Electrets.

Three-dimensional (3D) printing technology is advantageous in the fast prototyping of complex structures, but its utilization in functional material fabrication is still limited due to a lack of activation capability. To fabricate and activate the functional material of electrets, a synchronized 3D printing and corona charging method is presented to prototype and polarize polylactic acid electrets in one step. By upgrading the 3D printer nozzle and incorporating a needle electrode to apply high voltage, parameters such as needle tip distance and applied voltage level were compared and optimized. Under different experimental conditions, the average surface distribution in the center of the samples was -1498.87 V, -1115.73 V, and -814.51 V. Scanning electron microscopy results showed that the electric field contributes to keeping the printed fiber structure straight. The polylactic acid electrets exhibited relatively uniform surface potential distribution on a sufficiently large sample surface. In addition, the average surface potential retention rate was improved by 12.021-fold compared to ordinary corona-charged samples. The above advantages are unique to the 3D-printed and polarized polylactic acid electrets, proving that the proposed method is suitable for quickly prototyping and effectively polarizing the polylactic acid electrets simultaneously.