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AUTHOR Habelt, Bettina and Wirth, Christopher and Afanasenkau, Dzmitry and Mihaylova, Lyudmila and Winter, Christine and Arvaneh, Mahnaz and Minev, Ivan R. and Bernhardt, Nadine
Title A Multimodal Neuroprosthetic Interface to Record, Modulate and Classify Electrophysiological Biomarkers Relevant to Neuropsychiatric Disorders [Abstract]
Year 2021
Journal/Proceedings Frontiers in Bioengineering and Biotechnology
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Most mental disorders, such as addictive diseases or schizophrenia, are characterized by impaired cognitive function and behavior control originating from disturbances within prefrontal neural networks. Their often chronic reoccurring nature and the lack of efficient therapies necessitate the development of new treatment strategies. Brain-computer interfaces, equipped with multiple sensing and stimulation abilities, offer a new toolbox whose suitability for diagnosis and therapy of mental disorders has not yet been explored. This study, therefore, aimed to develop a biocompatible and multimodal neuroprosthesis to measure and modulate prefrontal neurophysiological features of neuropsychiatric symptoms. We used a 3D-printing technology to rapidly prototype customized bioelectronic implants through robot-controlled deposition of soft silicones and a conductive platinum ink. We implanted the device epidurally above the medial prefrontal cortex of rats and obtained auditory event-related brain potentials in treatment-naïve animals, after alcohol administration and following neuromodulation through implant-driven electrical brain stimulation and cortical delivery of the anti-relapse medication naltrexone. Towards smart neuroprosthetic interfaces, we furthermore developed machine learning algorithms to autonomously classify treatment effects within the neural recordings. The neuroprosthesis successfully captured neural activity patterns reflecting intact stimulus processing and alcohol-induced neural depression. Moreover, implant-driven electrical and pharmacological stimulation enabled successful enhancement of neural activity. A machine learning approach based on stepwise linear discriminant analysis was able to deal with sparsity in the data and distinguished treatments with high accuracy. Our work demonstrates the feasibility of multimodal bioelectronic systems to monitor, modulate and identify healthy and affected brain states with potential use in a personalized and optimized therapy of neuropsychiatric disorders.
AUTHOR Afanasenkau, Dzmitry and Kalinina, Daria and Lyakhovetskii, Vsevolod and Tondera, Christoph and Gorsky, Oleg and Moosavi, Seyyed and Pavlova, Natalia and Merkulyeva, Natalia and Kalueff, Allan V. and Minev, Ivan R. and Musienko, Pavel
Title Rapid prototyping of soft bioelectronic implants for use as neuromuscular interfaces [Abstract]
Year 2020
Journal/Proceedings Nature Biomedical Engineering
Reftype Afanasenkau2020
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Neuromuscular interfaces are required to translate bioelectronic technologies for application in clinical medicine. Here, by leveraging the robotically controlled ink-jet deposition of low-viscosity conductive inks, extrusion of insulating silicone pastes and in situ activation of electrode surfaces via cold-air plasma, we show that soft biocompatible materials can be rapidly printed for the on-demand prototyping of customized electrode arrays well adjusted to specific anatomical environments, functions and experimental models. We also show, with the monitoring and activation of neuronal pathways in the brain, spinal cord and neuromuscular system of cats, rats and zebrafish, that the printed bioelectronic interfaces allow for long-term integration and functional stability. This technology might enable personalized bioelectronics for neuroprosthetic applications.
AUTHOR Kleger, Nicole and Cihova, Martina and Masania, Kunal and Studart, André R. and Löffler, Jörg F.
Title 3d printing of salt as a template for magnesium with structured porosity [Abstract]
Year 2019
Journal/Proceedings advanced materials
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Abstract Porosity is an essential feature in a wide range of applications that combine light weight with high surface area and tunable density. Porous materials can be easily prepared with a vast variety of chemistries using the salt-leaching technique. However, this templating approach has so far been limited to the fabrication of structures with random porosity and relatively simple macroscopic shapes. Here, a technique is reported that combines the ease of salt leaching with the complex shaping possibilities given by additive manufacturing (AM). By tuning the composition of surfactant and solvent, the salt-based paste is rheologically engineered and printed via direct ink writing into grid-like structures displaying structured pores that span from the sub-millimeter to the macroscopic scale. As a proof of concept, dried and sintered NaCl templates are infiltrated with magnesium (Mg), which is typically highly challenging to process by conventional AM techniques due to its highly oxidative nature and high vapor pressure. Mg scaffolds with well-controlled, ordered porosity are obtained after salt removal. The tunable mechanical properties and the potential to be predictably bioresorbed by the human body make these Mg scaffolds attractive for biomedical implants and demonstrate the great potential of this additive technique.
AUTHOR Zhang, Danwei and Jonhson, Win and Herng, Tun Seng and Ang, Yong Quan and Yang, Lin and Tan, Swee Ching and Peng, Erwin and He, Hui and Ding, Jun
Title A 3D-printing method of fabrication for metals{,} ceramics{,} and multi-materials using a universal self-curable technique for robocasting [Abstract]
Year 2019
Journal/Proceedings Materials Horizons
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Ceramics and metals are important materials that modern technologies are constructed from. The capability to produce such materials in a complex geometry with good mechanical properties can revolutionize the way we engineer our devices. Current curing techniques pose challenges such as high energy requirements{,} limitations of materials with high refractive index{,} tedious post-processing heat treatment processes{,} uneven drying shrinkages{,} and brittleness of green bodies. In this paper{,} a novel modified self-curable epoxide–amine 3D printing system is proposed to print a wide range of ceramics (metal oxides{,} nitrides{,} and carbides) and metals without the need for an external curing source. Through this technique{,} complex multi-material structures (with metal–ceramic and ceramic–ceramic combinations) can also be realized. Tailoring and matching the sintering temperatures of different materials through sintering additives and dopants{,} combined with a structural design providing maximum adhesion between interfaces{,} allow us to successfully obtain superior quality sintered multi-material structures. High-quality ceramic and metallic materials have been achieved (e.g.{,} zirconia with >98% theoretical density). Also{,} highly conductive metals and magnetic ceramics were printed and shaped uniquely without the need for a sacrificial support. With the addition of low molecular weight plasticizers and a multi-stage heat treatment process{,} crack-free and dense high-quality integrated multi-material structures fabricated by 3D printing can thus be a reality in the near future.
AUTHOR Liu, Guangde and Yu, Rongrong and Liu, Dong and Xia, Yuanhua and Pei, Xiaoyuan and Wang, Wei and Min, Chunying and Liu, Shengkai and Shao, Ruiqi and Xu, Zhiwei
Title 3D-printed TiO2-Ti3C2Tx heterojunction/rGO/PDMS composites with gradient pore size for electromagnetic interference shielding and thermal management [Abstract]
Year 2022
Journal/Proceedings Composites Part A: Applied Science and Manufacturing
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In this paper, the Ti3C2Tx/GO frame with vertical pore gradient is constructed by using 3D printing technology. The TiO2-Ti3C2Tx heterojunctions is generated in situ by thermal annealing to control the oxidation of 3D frames. TiO2-Ti3C2Tx/rGO/PDMS composites with high EMI SE and excellent thermal management performance are assembled by curing the annealed 3D frame with polydimethylsiloxane (PDMS). Notably, the composites have a unique multilayer-scale structure that rod-shaped TiO2 particles are decorated on Ti3C2Tx substrate and TiO2-Ti3C2Tx/rGO stack to form an amorphous porous gradient pore size structure. The effect of gradient pore size on EMI SE of composites is studied by simulation. Under the synergistic effect of multiple loss mechanism, the designed composites show conductivity of up to 173.1 S/m, the thickness of the composite is 2 mm and the density is 67mg/cm3, which shows excellent EMI SE of 58 dB. The composites also have excellent thermal management performance.
AUTHOR Kim, Jieun and Lee, Joohyung
Title Liquid-Suspended and Liquid-Bridged Liquid Metal Microdroplets [Abstract]
Year 2022
Journal/Proceedings Small
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Abstract Liquid metals (LMs) and alloys are attracting increasing attention owing to their combined advantages of high conductivity and fluidity, and have shown promising results in various emerging applications. Patterning technologies using LMs are being actively researched; among them, direct ink writing is considered a potentially viable approach for efficient LM additive manufacturing. However, true LM additive manufacturing with arbitrary printing geometries remains challenging because of the intrinsically low rheological strength of LMs. Herein, colloidal suspensions of LM droplets amenable to additive manufacturing (or “3D printing”) are realized using formulations containing minute amounts of liquid capillary bridges. The resulting LM suspensions exhibit exceptionally high rheological strength with yield stress values well above 103 Pa, attributed to inter-droplet capillary attraction mediated by the liquid bridges adsorbed on the oxide skin of the LM droplets. Such liquid-bridged LM suspensions, as extrudable ink-type filaments, are based on uncurable continuous-phase liquid media, have a long pot-life and outstanding shear-thinning properties, and shape retention, demonstrating excellent rheological processability suitable for 3D printing. These findings will enable the emergence of a variety of new advanced applications that necessitate LM patterning into highly complicated multidimensional structures.
AUTHOR Wibowo, Arie and Tajalla, Gusti U. N. and Marsudi, Maradhana A. and Cooper, Glen and Asri, Lia A.T.W. and Liu, Fengyuan and Ardy, Husaini and Bartolo, Paulo J.D.S.
Title Green Synthesis of Silver Nanoparticles Using Extract of Cilembu Sweet Potatoes (Ipomoea batatas L var. Rancing) as Potential Filler for 3D Printed Electroactive and Anti-Infection Scaffolds [Abstract]
Year 2021
Journal/Proceedings Molecules
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Electroactive biomaterials are fascinating for tissue engineering applications because of their ability to deliver electrical stimulation directly to cells, tissue, and organs. One particularly attractive conductive filler for electroactive biomaterials is silver nanoparticles (AgNPs) because of their high conductivity, antibacterial activity, and ability to promote bone healing. However, production of AgNPs involves a toxic reducing agent which would inhibit biological scaffold performance. This work explores facile and green synthesis of AgNPs using extract of Cilembu sweet potato and studies the effect of baking and precursor concentrations (1, 10 and 100 mM) on AgNPs’ properties. Transmission electron microscope (TEM) results revealed that the smallest particle size of AgNPs (9.95 ± 3.69 nm) with nodular morphology was obtained by utilization of baked extract and ten mM AgNO3. Polycaprolactone (PCL)/AgNPs scaffolds exhibited several enhancements compared to PCL scaffolds. Compressive strength was six times greater (3.88 ± 0.42 MPa), more hydrophilic (contact angle of 76.8 ± 1.7°), conductive (2.3 ± 0.5 × 10−3 S/cm) and exhibited anti-bacterial properties against Staphylococcus aureus ATCC3658 (99.5% reduction of surviving bacteria). Despite the promising results, further investigation on biological assessment is required to obtain comprehensive study of this scaffold. This green synthesis approach together with the use of 3D printing opens a new route to manufacture AgNPs-based electroactive with improved anti-bacterial properties without utilization of any toxic organic solvents.
AUTHOR Zhang, Danwei and Jonhson, Win and Herng, Tun Seng and Xu, Xi and Liu, Xiaojing and Pan, Liang-ming and He, Hui and Ding, Jun
Title High Temperature Co-firing of 3D-Printed Al-ZnO/Al2O3 Multi-Material Two-Phase Flow Sensor [Abstract]
Year 2021
Journal/Proceedings Journal of Materiomics
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Sensors are crucial in the understanding of machines working under high temperatures and high-pressure conditions. Current devices utilize polymeric materials as electrical insulators which pose a challenge in the device’s lifespan. Ceramics, on the other hand, is robust and able to withstand high temperature and pressure. For such applications, a co-fired ceramic device which can provide both electrical conductivity and insulation is beneficial and acts as a superior candidate for sensor devices. In this paper, we propose a novel fabrication technique of complex multi-ceramics structures via 3D printing. This fabrication methodology increases both the geometrical complexity and the device’s shape precision. Structural ceramics (alumina) was employed as the electrical insulator whilst providing mechanical rigidity while a functional ceramic (alumina-doped zinc oxide) was employed as the electrically conductive material. The addition of sintering additives, tailoring the printing pastes’ solid loadings and heat treatment profile resolves multi-materials printing challenges such as shrinkage disparity and densification matching. Through high-temperature co-firing of ceramics (HTCC) technology, dense high quality functional multi-ceramics structures are achieved. The proposed fabrication methodology paves the way for multi-ceramics sensors to be utilized in high temperature and pressure systems in the near future.
AUTHOR García-Astrain, Clara and Lenzi, Elisa and Jimenez de Aberasturi, Dorleta and Henriksen-Lacey, Malou and Binelli, Marco R. and Liz-Marzán, Luis M.
Title 3D-Printed Biocompatible Scaffolds with Built-In Nanoplasmonic Sensors [Abstract]
Year 2020
Journal/Proceedings Advanced Functional Materials
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Abstract 3D printing strategies have acquired great relevance toward the design of 3D scaffolds with precise macroporous structures, for supported mammalian cell growth. Despite advances in 3D model designs, there is still a shortage of detection tools to precisely monitor in situ cell behavior in 3D, thereby allowing a better understanding of the progression of diseases or to test the efficacy of drugs in a more realistic microenvironment. Even if the number of available inks has exponentially increased, they do not necessarily offer the required functionalities to be used as internal sensors. Herein the potential of surface-enhanced Raman scattering (SERS) spectroscopy for the detection of biorelevant analytes within a plasmonic hydrogel-based, 3D-printed scaffold is demonstrated. Such SERS-active scaffolds allow for the 3D detection of model molecules, such as 4-mercaptobenzoic acid. Flexibility in the choice of plasmonic nanoparticles is demonstrated through the use of gold nanoparticles with different morphologies, gold nanorods showing the best balance between SERS enhancement and scaffold transparency. Detection of the biomarker adenosine is also demonstrated as a proof-of-concept toward the use of these plasmonic scaffolds for SERS sensing of cell-secreted molecules over extended periods of time.
AUTHOR Athanasiadis, Markos and Afanasenkau, Dzmitry and Derks, Wouter and Tondera, Christoph and Murganti, Francesca and Busskamp, Volker and Bergmann, Olaf and Minev, Ivan R.
Title Printed elastic membranes for multimodal pacing and recording of human stem-cell-derived cardiomyocytes [Abstract]
Year 2020
Journal/Proceedings npj Flexible Electronics
Reftype Athanasiadis2020
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Bioelectronic interfaces employing arrays of sensors and bioactuators are promising tools for the study, repair and engineering of cardiac tissues. They are typically constructed from rigid and brittle materials processed in a cleanroom environment. An outstanding technological challenge is the integration of soft materials enabling a closer match to the mechanical properties of biological cells and tissues. Here we present an algorithm for direct writing of elastic membranes with embedded electrodes, optical waveguides and microfluidics using a commercial 3D printing system and a palette of silicone elastomers. As proof of principle, we demonstrate interfacing of cardiomyocytes derived from human induced pluripotent stem cells (hiPSCs), which are engineered to express Channelrhodopsin-2. We demonstrate electrical recording of cardiomyocyte field potentials and their concomitant modulation by optical and pharmacological stimulation delivered via the membrane. Our work contributes a simple prototyping strategy with potential applications in organ-on-chip or implantable systems that are multi-modal and mechanically soft.
AUTHOR Nasim Golafshan and Elke Vorndran and Stefan Zaharievski and Harold Brommer and Firoz Babu Kadumudi and Alireza Dolatshahi-Pirouz and Uwe Gbureck and René {van Weeren} and Miguel Castilho and Jos Malda
Title Tough magnesium phosphate-based 3D-printed implants induce bone regeneration in an equine defect model [Abstract]
Year 2020
Journal/Proceedings Biomaterials
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One of the important challenges in bone tissue engineering is the development of biodegradable bone substitutes with appropriate mechanical and biological properties for the treatment of larger defects and those with complex shapes. Recently, magnesium phosphate (MgP) doped with biologically active ions like strontium (Sr2+) have shown to significantly enhance bone formation when compared with the standard calcium phosphate-based ceramics. However, such materials can hardly be shaped into large and complex geometries and more importantly lack the adequate mechanical properties for the treatment of load-bearing bone defects. In this study, we have fabricated bone implants through extrusion assisted three-dimensional (3D) printing of MgP ceramics modified with Sr2+ ions (MgPSr) and a medical grade polycaprolactone (PCL) polymer phase. MgPSr with 30 wt% PCL (MgPSr-PCL30) allowed the printability of relevant size structures (>780 mm3) at room temperature with an interconnected macroporosity of approximately 40%. The printing resulted in implants with a compressive strength of 4.3 MPa, which were able to support up to 50 cycles of loading without plastic deformation. Notably, MgPSr-PCL30 scaffolds were able to promote in vitro bone formation in medium without the supplementation with osteo-inducing components. In addition, long-term in vivo performance of the 3D printed scaffolds was investigated in an equine tuber coxae model over 6 months. The micro-CT and histological analysis showed that implantation of MgPSr-PCL30 induced bone regeneration, while no bone formation was observed in the empty defects. Overall, the novel polymer modified MgP ceramic material and extrusion-based 3D printing process presented here greatly improved the shape ability and load bearing properties of MgP-based ceramics with simultaneously induction of new bone formation.
AUTHOR Shen, Jie and Wang, Wenhao and Zhai, Xinyun and Chen, Bo and Qiao, Wei and Li, Wan and Li, Penghui and Zhao, Ying and Meng, Yuan and Qian, Shi and Liu, Xuanyong and Chu, Paul K. and Yeung, Kelvin W. K.
Title 3D-printed nanocomposite scaffolds with tunable magnesium ionic microenvironment induce in situ bone tissue regeneration [Abstract]
Year 2019
Journal/Proceedings Applied Materials Today
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Local tissue microenvironment is able to regulate cell-to-cell interaction that leads to effective tissue repair. This study aims to demonstrate a tunable magnesium ionic (Mg2+) microenvironment in bony tissue that can significantly induce bone defect repair. The concept can be realized by using a newly fabricated nanocomposite comprising of custom-made copolymer polycaprolactone-co-poly(ethylene glycol)-co-polycaprolactone (PCL-PEG-PCL) and surface-modified magnesium oxide (MgO) nanoparticles. In this study, additive manufacturing (AM) technology had been adopted to help design the porous three-dimensional (3D) scaffolds with tunable Mg2+ microenvironment. We found that the wettability and printability of new copolymer had been improved as compared with that of PCL polymer. Additionally, when MgO nanoparticles incorporated into the newly synthesized hydrophilic copolymer matrix, it could lead to increased compressive moduli significantly. In the in vitro studies, the fabricated nanocomposite scaffold with low concentration of Mg2+ microenvironment not only demonstrated better cytocompatibility, but also remarkably enhanced osteogenic differentiation in vitro as compared with the pure PCL and PCL-PEG-PCL co-polymer controls. In the animal studies, we also found that superior and early bone formation and tissue mineralization could be observed in the same 3D printed scaffold. However, the nanocomposite scaffold with high concentration of Mg2+ jeopardized the in situ bony tissue regeneration capability due to excessive magnesium ions in bone tissue microenvironment. Lastly, this study demonstrates that the nanocomposite 3D scaffold with controlled magnesium concentration in bone tissue microenvironment can effectively promote bone defect repair.
AUTHOR Augurio, Adriana and Cortelletti, Paolo and Tognato, Riccardo and Rios, Anne and Levato, Riccardo and Malda, Jos and Alini, Mauro and Eglin, David and Giancane, Gabriele and Speghini, Adolfo and Serra, Tiziano
Title A Multifunctional Nanocomposite Hydrogel for Endoscopic Tracking and Manipulation [Abstract]
Year 2019
Journal/Proceedings Advanced Intelligent Systems
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In this work, the fabrication of multi-responsive and hierarchically organized nanomaterial by using core-shell SrF2 upconverting nanoparticles, doped with Yb3+, Tm3+, Nd3+ incorporated into gelatin methacryloyl matrix, is reported. Upon 800 nm excitation, deep monitoring of 3D printed constructs is demonstrated. Addition of magnetic self-assembly of iron oxide nanoparticles within the hydrogel provides anisotropic structuration from the nano- to the macro-scale and magnetic responsiveness permitting remote manipulation. The present study provides a new strategy for the fabrication of a novel highly organized multi-responsive material using additive manufacturing, which could have important implications in biomedicine. This article is protected by copyright. All rights reserved.
AUTHOR Agarwala, Shweta and Lee, Jia Min and Ng, Wei Long and Layani, Michael and Yeong, Wai Yee and Magdassi, Shlomo
Title A novel 3D bioprinted flexible and biocompatible hydrogel bioelectronic platform [Abstract]
Year 2018
Journal/Proceedings Biosensors and Bioelectronics
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Abstract Bioelectronics platforms are gaining widespread attention as they provide a template to study the interactions between biological species and electronics. Decoding the effect of the electrical signals on the cells and tissues holds the promise for treating the malignant tissue growth, regenerating organs and engineering new-age medical devices. This work is a step forward in this direction, where bio- and electronic materials co-exist on one platform without any need for post processing. We fabricate a freestanding and flexible hydrogel based platform using 3D bioprinting. The fabrication process is simple, easy and provides a flexible route to print materials with preferred shapes, size and spatial orientation. Through the design of interdigitated electrodes and heating coil, the platform can be tailored to print various circuits for different functionalities. The biocompatibility of the printed platform is tested using C2C12 murine myoblasts cell line. Furthermore, normal human dermal fibroblasts (primary cells) are also seeded on the platform to ascertain the compatibility.
AUTHOR Tognato, Riccardo and Armiento, Angela R. and Bonfrate, Valentina and Levato, Riccardo and Malda, Jos and Alini, Mauro and Eglin, David and Giancane, Gabriele and Serra, Tiziano
Title A Stimuli-Responsive Nanocomposite for 3D Anisotropic Cell-Guidance and Magnetic Soft Robotics [Abstract]
Year 2018
Journal/Proceedings Advanced Functional Materials
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Abstract Stimuli-responsive materials have the potential to enable the generation of new bioinspired devices with unique physicochemical properties and cell-instructive ability. Enhancing biocompatibility while simplifying the production methodologies, as well as enabling the creation of complex constructs, i.e., via 3D (bio)printing technologies, remains key challenge in the field. Here, a novel method is presented to biofabricate cellularized anisotropic hybrid hydrogel through a mild and biocompatible process driven by multiple external stimuli: magnetic field, temperature, and light. A low-intensity magnetic field is used to align mosaic iron oxide nanoparticles (IOPs) into filaments with tunable size within a gelatin methacryloyl matrix. Cells seeded on top or embedded within the hydrogel align to the same axes of the IOPs filaments. Furthermore, in 3D, C2C12 skeletal myoblasts differentiate toward myotubes even in the absence of differentiation media. 3D printing of the nanocomposite hydrogel is achieved and creation of complex heterogeneous structures that respond to magnetic field is demonstrated. By combining the advanced, stimuli-responsive hydrogel with the architectural control provided by bioprinting technologies, 3D constructs can also be created that, although inspired by nature, express functionalities beyond those of native tissue, which have important application in soft robotics, bioactuators, and bionic devices.
AUTHOR Bastola, A. K. and Paudel, M. and Li, L.
Title Development of hybrid magnetorheological elastomers by 3D printing [Abstract]
Year 2018
Journal/Proceedings Polymer
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Intelligent or smart materials have one or more properties that can be significantly changed in a controlled fashion by external stimuli, such as temperature, pH, electric or magnetic fields, etc. Magnetorheological (MR) materials are a class of smart materials whose properties can be varied by applying an external magnetic field. In this work, the possibility of employing a suitable 3D printing technology for the development of one of the smart MR materials, the magnetorheological elastomer (MRE) has been explored. In order to achieve such 3D printing, a multi-material printing is implemented, where a controlled volume of MR fluid is encapsulated within an elastomer matrix in the layer-by-layer fashion. The choice of printing materials determines the final structure of the 3D printed hybrid MR elastomer. Printing with a vulcanizing MR suspension produces the solid MR structure inside the elastomer matrix while printing with a non-vulcanizing MR suspension (MR fluid) results in the structures that the MR fluid is encapsulated inside the elastomer matrix. The 3D printability of different materials has been studied by measuring their rheological properties and we found that the highly shear thinning and thixotropic properties are important for 3D printability. The quality of the printed filaments strongly depends on the key printing parameters such as extrusion pressure, initial height and feed rate. The experimental results from the forced vibration testing show that the 3D printed MR elastomers could change their elastic and damping properties when exposed to the external magnetic field. Furthermore, the 3D printed MR elastomer also exhibits the anisotropic behavior when the direction of the magnetic field is changed with respect to the orientation of the printed filaments. This study has demonstrated that the 3D printing is viable for fabrication of hybrid MR elastomers with controlled structures of magnetic particles or MR fluids.
AUTHOR Bastola, A. K. and Hoang, V. T. and Li, L.
Title A novel hybrid magnetorheological elastomer developed by 3D printing [Abstract]
Year 2017
Journal/Proceedings Materials and Design
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Abstract In this study, a novel magnetorheological (MR) hybrid elastomer has been developed using a 3D printing method. In such an MR hybrid elastomer, a controlled volume of an MR fluid was encapsulated layer by layer into an elastomer matrix by means of a 3D printer and each layer was a composite structure consisting of an MR fluid and an elastomer. Similar to current MR fluids and MR elastomers, mechanical properties of 3D printed MR hybrid elastomers could be controlled via an externally applied magnetic field. The experimental results showed that the relative change in the damping capability of the new MR elastomer was more pronounced than the change in its stiffness when exposed to an external magnetic field. The study demonstrated that the 3D printing technique is feasible for fabrication of MR elastomers with controlled microstructures including magnetic particles or MR fluids. The 3D printed MR hybrid elastomer is also a potential material as a tunable spring-damper element.