2025
A. Zanini; G. Bombardelli; G. Giometti; A. De Marzi; J. Erler; D. Nissen; G. Franchin; P. Colombo
Additive Manufacturing of Multicomponent Glasses with Enhanced Optical Properties via Sol-Gel Journal Article
In: Additive Manufacturing, 2025, ISSN: 2214-8604.
Links | BibTeX | Tags: Additive Manufacturing
@article{Zanini2025,
title = {Additive Manufacturing of Multicomponent Glasses with Enhanced Optical Properties via Sol-Gel},
author = {A. Zanini and G. Bombardelli and G. Giometti and A. De Marzi and J. Erler and D. Nissen and G. Franchin and P. Colombo},
doi = {10.1016/j.addma.2025.104864},
issn = {2214-8604},
year = {2025},
date = {2025-06-00},
urldate = {2025-06-00},
journal = {Additive Manufacturing},
publisher = {Elsevier BV},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
A. De Marzi; F. Da Rin Betta; G. Franchin; R. M. Seabright; C. J. Footer; P. Colombo
Fabrication of continuous fiber reinforced ceramic matrix mini‐composites via direct ink writing Journal Article
In: J Am Ceram Soc., 2025, ISSN: 1551-2916.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{DeMarzi2025,
title = {Fabrication of continuous fiber reinforced ceramic matrix mini‐composites via direct ink writing},
author = {A. De Marzi and F. Da Rin Betta and G. Franchin and R. M. Seabright and C. J. Footer and P. Colombo},
doi = {10.1111/jace.20696},
issn = {1551-2916},
year = {2025},
date = {2025-05-26},
urldate = {2025-05-26},
journal = {J Am Ceram Soc.},
publisher = {Wiley},
abstract = {<jats:title>Abstract</jats:title><jats:p>Ceramic materials are valued for their exceptional heat and corrosion resistance, yet their inherent brittleness limits their use in applications requiring high strength‐to‐weight ratios, fatigue resistance, and durability under harsh conditions, such as those in the aerospace and automotive industries. The development of ceramic matrix composites (CMCs), incorporating continuous reinforcements, has enhanced the mechanical performance of ceramics, offering superior toughness compared to randomly oriented composites. Traditional fabrication methods for composites, such as polymer infiltration and pyrolysis (PIP) and chemical vapor infiltration (CVI), are effective but constrained by shaping complexities. Direct ink writing (DIW) has emerged as a fabrication approach for CMCs fabrication, enabling custom geometries and tailored reinforcement architectures. Extrusion‐based processes naturally align fibers, optimizing their orientation and enhancing composite properties. This study focuses on the fabrication of silicon oxycarbide matrix reinforced with continuous carbon fibers using two DIW approaches. Comparative analysis highlighted the benefits and limitations of each method, with post‐processing via PIP addressing crack formation and improving densification. Mechanical properties were evaluated at different fabrication stages, revealing key relationships between processing techniques and final composite performance.</jats:p>},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
<jats:title>Abstract</jats:title><jats:p>Ceramic materials are valued for their exceptional heat and corrosion resistance, yet their inherent brittleness limits their use in applications requiring high strength‐to‐weight ratios, fatigue resistance, and durability under harsh conditions, such as those in the aerospace and automotive industries. The development of ceramic matrix composites (CMCs), incorporating continuous reinforcements, has enhanced the mechanical performance of ceramics, offering superior toughness compared to randomly oriented composites. Traditional fabrication methods for composites, such as polymer infiltration and pyrolysis (PIP) and chemical vapor infiltration (CVI), are effective but constrained by shaping complexities. Direct ink writing (DIW) has emerged as a fabrication approach for CMCs fabrication, enabling custom geometries and tailored reinforcement architectures. Extrusion‐based processes naturally align fibers, optimizing their orientation and enhancing composite properties. This study focuses on the fabrication of silicon oxycarbide matrix reinforced with continuous carbon fibers using two DIW approaches. Comparative analysis highlighted the benefits and limitations of each method, with post‐processing via PIP addressing crack formation and improving densification. Mechanical properties were evaluated at different fabrication stages, revealing key relationships between processing techniques and final composite performance.</jats:p>
C. Gravino; N. Gargiulo; A. Peluso; P. Aprea; M. D'Agostini; G. Franchin; P. Colombo; D. Caputo
Equilibrium adsorption behaviour of a 3D-printed zeolite–geopolymer composite with high faujasitic content Journal Article
In: Mater. Adv., vol. 6, no. 8, pp. 2579–2587, 2025, ISSN: 2633-5409.
Abstract | Links | BibTeX | Tags: Additive Manufacturing, Materials for the environment
@article{Gravino2025,
title = {Equilibrium adsorption behaviour of a 3D-printed zeolite–geopolymer composite with high faujasitic content},
author = {C. Gravino and N. Gargiulo and A. Peluso and P. Aprea and M. D'Agostini and G. Franchin and P. Colombo and D. Caputo},
doi = {10.1039/d4ma01074d},
issn = {2633-5409},
year = {2025},
date = {2025-04-14},
urldate = {2025-04-14},
journal = {Mater. Adv.},
volume = {6},
number = {8},
pages = {2579--2587},
publisher = {Royal Society of Chemistry (RSC)},
abstract = {<jats:p>A potential CO<jats:sub>2</jats:sub> and water vapour adsorbent made of a NaX zeolite/Na-activated geopolymer composite material was fabricated as 3D-printed monoliths by means of Direct Ink Writing.</jats:p>},
keywords = {Additive Manufacturing, Materials for the environment},
pubstate = {published},
tppubtype = {article}
}
<jats:p>A potential CO<jats:sub>2</jats:sub> and water vapour adsorbent made of a NaX zeolite/Na-activated geopolymer composite material was fabricated as 3D-printed monoliths by means of Direct Ink Writing.</jats:p>
S. Bhandari; G. Vajpayee; L. Lemos Silva; M. Hinterstein; G. Franchin; P. Colombo
A review on additive manufacturing of piezoelectric ceramics: From feedstock development to properties of sintered parts Journal Article
In: Materials Science and Engineering: R: Reports, vol. 162, pp. 100877, 2025, ISSN: 0927-796X.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{BHANDARI2025100877,
title = {A review on additive manufacturing of piezoelectric ceramics: From feedstock development to properties of sintered parts},
author = {S. Bhandari and G. Vajpayee and L. Lemos Silva and M. Hinterstein and G. Franchin and P. Colombo},
url = {https://www.sciencedirect.com/science/article/pii/S0927796X24001074},
doi = {https://doi.org/10.1016/j.mser.2024.100877},
issn = {0927-796X},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {Materials Science and Engineering: R: Reports},
volume = {162},
pages = {100877},
abstract = {Piezoelectric ceramics are extensively used in several engineering applications in the field of sensors, actuators, energy harvesting, biomedical, and many more. Traditional ways of manufacturing piezoelectric devices result in better piezoelectric/ferroelectric performance. However, they are restricted to only simple shapes. With the widespread influence of additive manufacturing (AM), it is now possible to fabricate complex structures which were not possible by conventional technologies. In order to fabricate such complex structures with precision, it is necessary to understand in detail the factors influencing the feedstock preparation and the challenges associated with different AM technologies. With an emphasis on the most commonly used AM techniques (direct ink writing, fused filament fabrication, vat photopolymerization, binder jetting, and selective laser sintering) for fabricating ceramic parts, this review paper intends to provide a deep insight into the factors affecting the feedstock preparation as well as post-processing conditions required to develop a high-performance piezoelectric device. The summarized tables detailing the various piezoelectric ceramic compositions and additives or ingredients used in formulating a printable feedstock, along with the optimum printing and post-processing conditions, will aid the readers in developing their own printable formulations and determining the best post-processing parameters to achieve the best performance out of the fabricated piezoelectric device. The advantages and disadvantages of the AM technologies are analyzed with specific reference to piezoceramic materials and the remaining challenges that require further research are emphasized. Furthermore, with the ongoing and continuous developments in additive manufacturing of piezoelectric materials, it is expected that such advancements will progressively transition towards commercialization, with the ultimate goal of widely incorporating additively manufactured devices into practical applications.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Piezoelectric ceramics are extensively used in several engineering applications in the field of sensors, actuators, energy harvesting, biomedical, and many more. Traditional ways of manufacturing piezoelectric devices result in better piezoelectric/ferroelectric performance. However, they are restricted to only simple shapes. With the widespread influence of additive manufacturing (AM), it is now possible to fabricate complex structures which were not possible by conventional technologies. In order to fabricate such complex structures with precision, it is necessary to understand in detail the factors influencing the feedstock preparation and the challenges associated with different AM technologies. With an emphasis on the most commonly used AM techniques (direct ink writing, fused filament fabrication, vat photopolymerization, binder jetting, and selective laser sintering) for fabricating ceramic parts, this review paper intends to provide a deep insight into the factors affecting the feedstock preparation as well as post-processing conditions required to develop a high-performance piezoelectric device. The summarized tables detailing the various piezoelectric ceramic compositions and additives or ingredients used in formulating a printable feedstock, along with the optimum printing and post-processing conditions, will aid the readers in developing their own printable formulations and determining the best post-processing parameters to achieve the best performance out of the fabricated piezoelectric device. The advantages and disadvantages of the AM technologies are analyzed with specific reference to piezoceramic materials and the remaining challenges that require further research are emphasized. Furthermore, with the ongoing and continuous developments in additive manufacturing of piezoelectric materials, it is expected that such advancements will progressively transition towards commercialization, with the ultimate goal of widely incorporating additively manufactured devices into practical applications.
S. Bhandari; O. Hanzel; M. Kermani; V. M. Sglavo; M. Biesuz; G. Franchin
Rapid debinding and sintering of alumina ceramics fabricated by direct ink writing Journal Article
In: Journal of the European Ceramic Society, vol. 45, no. 5, pp. 117144, 2025, ISSN: 0955-2219.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{BHANDARI2025117144,
title = {Rapid debinding and sintering of alumina ceramics fabricated by direct ink writing},
author = {S. Bhandari and O. Hanzel and M. Kermani and V. M. Sglavo and M. Biesuz and G. Franchin},
url = {https://www.sciencedirect.com/science/article/pii/S0955221924010173},
doi = {https://doi.org/10.1016/j.jeurceramsoc.2024.117144},
issn = {0955-2219},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {Journal of the European Ceramic Society},
volume = {45},
number = {5},
pages = {117144},
abstract = {Direct ink writing (DIW) is a widely used additive manufacturing technique to fabricate complex-shaped ceramics. Unlike vat photopolymerization or fused filament fabrication, the limited amount of binder in DIW facilitates rapid debinding. In this study, alumina inks with suitable rheology were prepared with two different ceramic loadings (42.8 vol% and 48.1 vol%). Subsequently, log-pile structures were printed using two different nozzle diameters (0.41 mm and 0.84 mm). The fabricated samples were dried at room temperature and subjected to different rapid sintering procedures: ultra-fast high temperature sintering (UHS), pressureless spark plasma sintering (PSPS) and fast-firing (FF). Both UHS and PSPS successfully densified the samples in Ar without any defects. Conversely, the fast-firing in air resulted in some cracks, with the intensity of failures increasing with the nozzle size. UHS and PSPS allowed for nearly fully dense materials with refined microstructure which are not achievable by conventional heating.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Direct ink writing (DIW) is a widely used additive manufacturing technique to fabricate complex-shaped ceramics. Unlike vat photopolymerization or fused filament fabrication, the limited amount of binder in DIW facilitates rapid debinding. In this study, alumina inks with suitable rheology were prepared with two different ceramic loadings (42.8 vol% and 48.1 vol%). Subsequently, log-pile structures were printed using two different nozzle diameters (0.41 mm and 0.84 mm). The fabricated samples were dried at room temperature and subjected to different rapid sintering procedures: ultra-fast high temperature sintering (UHS), pressureless spark plasma sintering (PSPS) and fast-firing (FF). Both UHS and PSPS successfully densified the samples in Ar without any defects. Conversely, the fast-firing in air resulted in some cracks, with the intensity of failures increasing with the nozzle size. UHS and PSPS allowed for nearly fully dense materials with refined microstructure which are not achievable by conventional heating.
S. Bhandari; T. Heim; E. De Bona; V. M. Sglavo; W. Rheinheimer; M. Biesuz; G. Franchin
Rapid processing of Al2O3 ceramics by fused filament fabrication and ultrafast high-temperature debinding and sintering Journal Article
In: Journal of Alloys and Compounds, pp. 178812, 2025, ISSN: 0925-8388.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{BHANDARI2025178812,
title = {Rapid processing of Al2O3 ceramics by fused filament fabrication and ultrafast high-temperature debinding and sintering},
author = {S. Bhandari and T. Heim and E. De Bona and V. M. Sglavo and W. Rheinheimer and M. Biesuz and G. Franchin},
url = {https://www.sciencedirect.com/science/article/pii/S0925838825003706},
doi = {https://doi.org/10.1016/j.jallcom.2025.178812},
issn = {0925-8388},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {Journal of Alloys and Compounds},
pages = {178812},
abstract = {Fused filament fabrication (FFF) is widely used for ceramic prototyping due to its compatibility with low-cost, custom-made printers designed for polymers. However, the bottleneck of the whole process lies in the slow thermal debinding and sintering that are usually employed to obtain dense and defect-free ceramics. In this study, a filament with ~79wt.% alumina powder in a thermoplastic binder was used to print gyroid structures with nozzle diameters of 0.4, 0.6, and 0.8mm. The components were at first partially solvent-debinded (acetone) and thereafter thermally debinded and consolidated in a single step (60s) by ultra-fast high-temperature sintering. Samples printed with a 0.4mm nozzle diameter resisted the ultra-rapid heating (UHS) and cooling rates (~103K/min), whereas some defects appear when considering larger nozzle size. On the other hand, all samples either cracked or shattered into pieces when fast-fired in air, highlighting the relevance of the thermal debinding atmosphere. Moreover, the densification upon UHS was largely improved compared to conventional sintering while retaining a finer grain size. This work provides a guideline for the rapid debinding and firing of fused filament fabricated ceramics and could be easily extended to other ceramic systems.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Fused filament fabrication (FFF) is widely used for ceramic prototyping due to its compatibility with low-cost, custom-made printers designed for polymers. However, the bottleneck of the whole process lies in the slow thermal debinding and sintering that are usually employed to obtain dense and defect-free ceramics. In this study, a filament with ~79wt.% alumina powder in a thermoplastic binder was used to print gyroid structures with nozzle diameters of 0.4, 0.6, and 0.8mm. The components were at first partially solvent-debinded (acetone) and thereafter thermally debinded and consolidated in a single step (60s) by ultra-fast high-temperature sintering. Samples printed with a 0.4mm nozzle diameter resisted the ultra-rapid heating (UHS) and cooling rates (~103K/min), whereas some defects appear when considering larger nozzle size. On the other hand, all samples either cracked or shattered into pieces when fast-fired in air, highlighting the relevance of the thermal debinding atmosphere. Moreover, the densification upon UHS was largely improved compared to conventional sintering while retaining a finer grain size. This work provides a guideline for the rapid debinding and firing of fused filament fabricated ceramics and could be easily extended to other ceramic systems.
V. Diamanti; H. Elsayed; E. Bernardo
3D-printed porous mullite lattice structures by hybrid direct ink writing of silicone suspension-emulsions Journal Article
In: Journal of the American Ceramic Society, vol. 108, no. 4, pp. e20290, 2025.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{https://doi.org/10.1111/jace.20290,
title = {3D-printed porous mullite lattice structures by hybrid direct ink writing of silicone suspension-emulsions},
author = {V. Diamanti and H. Elsayed and E. Bernardo},
url = {https://ceramics.onlinelibrary.wiley.com/doi/abs/10.1111/jace.20290},
doi = {https://doi.org/10.1111/jace.20290},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {Journal of the American Ceramic Society},
volume = {108},
number = {4},
pages = {e20290},
abstract = {Abstract Silicones added with nano-sized alumina particles are already known as starting materials for phase pure mullite ceramics, synthesized at quite low temperatures. The present paper deals with a fundamental upgrade, based on a novel suspension-emulsion concept, for the easy fabrication of highly porous lattice structures. An aqueous suspension of γ-Al2O3 nanoparticles in water was first distributed as emulsion within an “oily phase,” consisting of a silicone/acrylates blend, with the help of a surfactant. The mixture was later employed to fabricate highly porous structures (∼80% open porosity), by direct ink writing, that is, an extrusion-based 3D printing technology requiring specific rheological behavior of the feedstock ink. Finally, the structures were rapidly stabilized through a photo-polymerization step (configuring a form of “hybrid” direct ink writing). The presence of water also allowed the application of a freeze-curing procedure, for a second series of samples. The abundant water vapor release from the starting mixtures, upon firing (up to 1300°C), led to structures with enhanced pore interconnectivity. The freeze-curing protocol proved beneficial to the homogeneity of pore distribution and to the achievement of high strength-to-density ratios.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Abstract Silicones added with nano-sized alumina particles are already known as starting materials for phase pure mullite ceramics, synthesized at quite low temperatures. The present paper deals with a fundamental upgrade, based on a novel suspension-emulsion concept, for the easy fabrication of highly porous lattice structures. An aqueous suspension of γ-Al2O3 nanoparticles in water was first distributed as emulsion within an “oily phase,” consisting of a silicone/acrylates blend, with the help of a surfactant. The mixture was later employed to fabricate highly porous structures (∼80% open porosity), by direct ink writing, that is, an extrusion-based 3D printing technology requiring specific rheological behavior of the feedstock ink. Finally, the structures were rapidly stabilized through a photo-polymerization step (configuring a form of “hybrid” direct ink writing). The presence of water also allowed the application of a freeze-curing procedure, for a second series of samples. The abundant water vapor release from the starting mixtures, upon firing (up to 1300°C), led to structures with enhanced pore interconnectivity. The freeze-curing protocol proved beneficial to the homogeneity of pore distribution and to the achievement of high strength-to-density ratios.
W. Wang; X. Gao; X. Chen; A. De Marzi; K. Huang; R. He; P. Colombo
Zhaozhou Bridge inspired embedded material extrusion 3D printing of Csf/SiC ceramic matrix composites Journal Article
In: Journal of the American Ceramic Society, 2025.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{Wang2025,
title = {Zhaozhou Bridge inspired embedded material extrusion 3D printing of Csf/SiC ceramic matrix composites},
author = {W. Wang and X. Gao and X. Chen and A. De Marzi and K. Huang and R. He and P. Colombo},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-105004352294&doi=10.1111%2fjace.20644&partnerID=40&md5=1118badf05310dcb65bf4ad0c3f26423},
doi = {10.1111/jace.20644},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {Journal of the American Ceramic Society},
abstract = {Material extrusion (MEX) 3D printing, while effective for many applications, faces challenges in fabricating arch shapes and suspended structures. This study advances MEX technology by drawing inspiration from ancient bridge construction techniques like the Zhaozhou Bridge, using an innovative embedded material extrusion (EMEX) method that eliminates the need for additional support structures in fabricating complex short carbon fiber reinforced SiC ceramic matrix composites (Csf/SiC CMCs). Utilizing solid powders as a supporting medium, EMEX enables the creation of intricate arch shapes and suspension structures, overcoming limitations associated with conventional MEX. The impact of supporting media (SiC powders and sugar) on the microstructure and mechanical properties of the composites was demonstrated. Residual SiC powders caused uneven material distribution, while residual sugar led to cracking. The presence of residual powders also influenced the shrinkage behavior and bending strength of the Csf/SiC CMCs, with a notable decrease observed when transitioning from air to SiC powders and then to sugar as the printing environment. The successful fabrication of Csf/SiC CMCs with complex geometries using EMEX indicates its potential as a promising supportless strategy for producing sophisticated CMC structures.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Material extrusion (MEX) 3D printing, while effective for many applications, faces challenges in fabricating arch shapes and suspended structures. This study advances MEX technology by drawing inspiration from ancient bridge construction techniques like the Zhaozhou Bridge, using an innovative embedded material extrusion (EMEX) method that eliminates the need for additional support structures in fabricating complex short carbon fiber reinforced SiC ceramic matrix composites (Csf/SiC CMCs). Utilizing solid powders as a supporting medium, EMEX enables the creation of intricate arch shapes and suspension structures, overcoming limitations associated with conventional MEX. The impact of supporting media (SiC powders and sugar) on the microstructure and mechanical properties of the composites was demonstrated. Residual SiC powders caused uneven material distribution, while residual sugar led to cracking. The presence of residual powders also influenced the shrinkage behavior and bending strength of the Csf/SiC CMCs, with a notable decrease observed when transitioning from air to SiC powders and then to sugar as the printing environment. The successful fabrication of Csf/SiC CMCs with complex geometries using EMEX indicates its potential as a promising supportless strategy for producing sophisticated CMC structures.
2024
S. M. Carturan; H. Skliarova; G. Franchin; G. Bombardelli; A. Zanini; F. E. P. Andrades; J. C. Delgado Alvarez; S. Moretto; G. Maggioni; W. Raniero; D. Maniglio; A. P. Caricato; A. Quaranta
Additive manufacturing of high-performance, flexible 3D siloxane-based scintillators through the sol-gel route Journal Article
In: Applied Materials Today, vol. 39, 2024, ISSN: 2352-9407.
Links | BibTeX | Tags: Additive Manufacturing
@article{Carturan2024,
title = {Additive manufacturing of high-performance, flexible 3D siloxane-based scintillators through the sol-gel route},
author = {S. M. Carturan and H. Skliarova and G. Franchin and G. Bombardelli and A. Zanini and F. E. P. Andrades and J. C. Delgado Alvarez and S. Moretto and G. Maggioni and W. Raniero and D. Maniglio and A. P. Caricato and A. Quaranta},
doi = {10.1016/j.apmt.2024.102313},
issn = {2352-9407},
year = {2024},
date = {2024-08-00},
urldate = {2024-08-00},
journal = {Applied Materials Today},
volume = {39},
publisher = {Elsevier BV},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
A. Zanini; P. Amador Celdran; O. Walter; S. M. Carturan; J. Boshoven; A. Bulgheroni; L. Biasetto; M. Manzolaro; R. Eloirdi; S. Corradetti; G. Franchin
First Structured Uranium‐Based Monoliths Produced via Vat Photopolymerization for Nuclear Applications Journal Article
In: Adv Funct Materials, 2024, ISSN: 1616-3028.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{Zanini2024,
title = {First Structured Uranium‐Based Monoliths Produced via Vat Photopolymerization for Nuclear Applications},
author = {A. Zanini and P. Amador Celdran and O. Walter and S. M. Carturan and J. Boshoven and A. Bulgheroni and L. Biasetto and M. Manzolaro and R. Eloirdi and S. Corradetti and G. Franchin},
doi = {10.1002/adfm.202406916},
issn = {1616-3028},
year = {2024},
date = {2024-06-20},
urldate = {2024-06-20},
journal = {Adv Funct Materials},
publisher = {Wiley},
abstract = {Uranium plays an unquestionable role in the framework of nuclear physics, biology, and radiopharmacy. Moreover, uranyl ion UO2 2+ offers an immense variety of applications due to the unique photosensitivity of its complexes. The excited state of uranyl cation is indeed accessible under ultraviolet‐visible (UV–vis) light, readily producing radical species UO2 2+ upon light irradiation. Herein, an innovative synthesis protocol is presented to explore the use of uranyl cations as photocatalyst systems for photocurable sol–gel‐based formulations, coupling the photochemical reactions of uranyl cations with photopolymerization‐based additive manufacturing processes. Additive manufacturing has nowadays revolutionized the production of complex structures with arbitrary geometries and has opened up enticing opportunities for innovative technological breakthroughs and highly tailorable systems. The fabrication of micro‐architected components is shown via vat photopolymerization, namely, the Digital Light Processing technique, and ‐3D) printed parts are converted into uranium dicarbide (UC2)/carbon nanocomposite upon carbothermal reduction. This uranyl‐mediated additive manufacturing process constitutes the first application of the synergistic role of uranyl motifs in a photopolymer platform, demonstrating for the first time the possibility to directly pattern uranium‐based materials in complex structures.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Uranium plays an unquestionable role in the framework of nuclear physics, biology, and radiopharmacy. Moreover, uranyl ion UO2 2+ offers an immense variety of applications due to the unique photosensitivity of its complexes. The excited state of uranyl cation is indeed accessible under ultraviolet‐visible (UV–vis) light, readily producing radical species UO2 2+ upon light irradiation. Herein, an innovative synthesis protocol is presented to explore the use of uranyl cations as photocatalyst systems for photocurable sol–gel‐based formulations, coupling the photochemical reactions of uranyl cations with photopolymerization‐based additive manufacturing processes. Additive manufacturing has nowadays revolutionized the production of complex structures with arbitrary geometries and has opened up enticing opportunities for innovative technological breakthroughs and highly tailorable systems. The fabrication of micro‐architected components is shown via vat photopolymerization, namely, the Digital Light Processing technique, and ‐3D) printed parts are converted into uranium dicarbide (UC2)/carbon nanocomposite upon carbothermal reduction. This uranyl‐mediated additive manufacturing process constitutes the first application of the synergistic role of uranyl motifs in a photopolymer platform, demonstrating for the first time the possibility to directly pattern uranium‐based materials in complex structures.
A. De Marzi; S. Diener; A. Campagnolo; G. Meneghetti; N. Katsikis; P. Colombo; G. Franchin
Ultra-lightweight silicon nitride truss-based structures fabricated via UV-assisted robot direct ink writing Journal Article
In: Materials & Design, pp. 113092, 2024, ISSN: 0264-1275.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{DEMARZI2024113092,
title = {Ultra-lightweight silicon nitride truss-based structures fabricated via UV-assisted robot direct ink writing},
author = {A. De Marzi and S. Diener and A. Campagnolo and G. Meneghetti and N. Katsikis and P. Colombo and G. Franchin},
url = {https://www.sciencedirect.com/science/article/pii/S0264127524004660},
doi = {https://doi.org/10.1016/j.matdes.2024.113092},
issn = {0264-1275},
year = {2024},
date = {2024-06-14},
urldate = {2024-06-14},
journal = {Materials & Design},
pages = {113092},
abstract = {Additive manufacturing techniques have gone beyond their reputation for rapid prototype production and are increasingly adopted for the manufacture of functional components comprising high-end materials and intricate lattice structures. Silicon nitride, renowned for its exceptional mechanical properties and thermal stability, has emerged as a promising candidate for lightweight structural applications. Nonetheless, its high refractive index and density have limited the fabrication of highly complex structures using extrusion and photopolymerization based techniques. In this work, a highly reactive silicon nitride-based ink with high solid loading is developed for the fabrication of ultra-lightweight, truss-based structures. By employing a robot UV-assisted direct ink writing process, it is possible to control the printing head orientation, thus overcoming the limited curing depth of silicon nitride-based inks. The failure behavior of the sintered lattice beam structures under 4-point bending loading has been modeled by applying a linear elastic fracture mechanics (LEFM) based approach to the results of finite element (FE) simulations.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Additive manufacturing techniques have gone beyond their reputation for rapid prototype production and are increasingly adopted for the manufacture of functional components comprising high-end materials and intricate lattice structures. Silicon nitride, renowned for its exceptional mechanical properties and thermal stability, has emerged as a promising candidate for lightweight structural applications. Nonetheless, its high refractive index and density have limited the fabrication of highly complex structures using extrusion and photopolymerization based techniques. In this work, a highly reactive silicon nitride-based ink with high solid loading is developed for the fabrication of ultra-lightweight, truss-based structures. By employing a robot UV-assisted direct ink writing process, it is possible to control the printing head orientation, thus overcoming the limited curing depth of silicon nitride-based inks. The failure behavior of the sintered lattice beam structures under 4-point bending loading has been modeled by applying a linear elastic fracture mechanics (LEFM) based approach to the results of finite element (FE) simulations.
S. Bhandari; O. Hanzel; P. Veteška; M. Janek; E. De Bona; V. M. Sglavo; M. Biesuz; G. Franchin
From rapid prototyping to rapid firing: on the feasibility of high‐speed production for complex BaTiO3 components Journal Article
In: J Am Ceram Soc., 2024, ISSN: 1551-2916.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{Bhandari2024,
title = {From rapid prototyping to rapid firing: on the feasibility of high‐speed production for complex BaTiO3 components},
author = {S. Bhandari and O. Hanzel and P. Veteška and M. Janek and E. De Bona and V. M. Sglavo and M. Biesuz and G. Franchin},
doi = {10.1111/jace.19950},
issn = {1551-2916},
year = {2024},
date = {2024-06-14},
urldate = {2024-06-14},
journal = {J Am Ceram Soc.},
publisher = {Wiley},
abstract = {Direct ink writing (DIW) is an attractive additive manufacturing (AM) technology because of its simplicity, production speed, and feedstock flexibility; in addition, the use of a limited amount of binder makes the subsequent thermal debinding process easy. Nevertheless, the conventional approach to debind and sinter AMed components remains extremely slow, representing a bottleneck in the manufacturing process. In order to address such limitation, we explored different rapid sintering strategies: ultrafast high‐temperature sintering (UHS), pressureless spark plasma sintering (P‐SPS), and fast firing (FF), for the densification of BaTiO<jats:sub>3</jats:sub> components fabricated by DIW, one of the widely used lead‐free piezoceramics. All sintering technologies allow debinding and sintering of crack‐free components in a few minutes instead of several hours. The final density and microstructure are strongly dependent on the sintering atmosphere (inert for UHS and P‐SPS, air for FF) and a maximum relative density of only ≈72% was obtained when firing occurred in an inert environment, irrespective of the sintering technique (UHS and P‐SPS). An undesired phase transition from tetragonal to hexagonal BaTiO<jats:sub>3</jats:sub> was also observed upon UHS and ‐PSPS. On the contrary, FF in air yielded a density of about 95% in a few minutes while maintaining the desired tetragonal polymorph. The results provide proof of feasibility for rapid processing of BaTiO<jats:sub>3</jats:sub> components obtained by DIW.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Direct ink writing (DIW) is an attractive additive manufacturing (AM) technology because of its simplicity, production speed, and feedstock flexibility; in addition, the use of a limited amount of binder makes the subsequent thermal debinding process easy. Nevertheless, the conventional approach to debind and sinter AMed components remains extremely slow, representing a bottleneck in the manufacturing process. In order to address such limitation, we explored different rapid sintering strategies: ultrafast high‐temperature sintering (UHS), pressureless spark plasma sintering (P‐SPS), and fast firing (FF), for the densification of BaTiO<jats:sub>3</jats:sub> components fabricated by DIW, one of the widely used lead‐free piezoceramics. All sintering technologies allow debinding and sintering of crack‐free components in a few minutes instead of several hours. The final density and microstructure are strongly dependent on the sintering atmosphere (inert for UHS and P‐SPS, air for FF) and a maximum relative density of only ≈72% was obtained when firing occurred in an inert environment, irrespective of the sintering technique (UHS and P‐SPS). An undesired phase transition from tetragonal to hexagonal BaTiO<jats:sub>3</jats:sub> was also observed upon UHS and ‐PSPS. On the contrary, FF in air yielded a density of about 95% in a few minutes while maintaining the desired tetragonal polymorph. The results provide proof of feasibility for rapid processing of BaTiO<jats:sub>3</jats:sub> components obtained by DIW.
K. Huang; G. Franchin; P. Colombo
Volumetric Additive Manufacturing of SiOC by Xolography Journal Article
In: Small, 2024, ISSN: 1613-6829.
Abstract | Links | BibTeX | Tags: Additive Manufacturing, Polymer-derived ceramics
@article{Huang2024,
title = {Volumetric Additive Manufacturing of SiOC by Xolography},
author = {K. Huang and G. Franchin and P. Colombo},
doi = {10.1002/smll.202402356},
issn = {1613-6829},
year = {2024},
date = {2024-05-10},
urldate = {2024-05-10},
journal = {Small},
publisher = {Wiley},
abstract = {Additive manufacturing (AM) of ceramics has significantly contributed to advancements in ceramic fabrication, solving some of the difficulties of conventional ceramic processing and providing additional possibilities for the structure and function of components. However, defects induced by the layer‐by‐layer approach on which traditional AM techniques are based still constitute a challenge to address. This study presents the volumetric AM of a SiOC ceramic from a preceramic polymer using xolography, a linear volumetric AM process that allows to avoid the staircase effect typical of other vat photopolymerization techniques. Besides optimizing the trade‐off between preceramic polymer content and transmittance, a pore generator is introduced to create transient channels for gas release before decomposition of the organic constituents and moieties, resulting in crack‐free solid ceramic structures even at low ceramic yield. Formulation optimization alleviated sinking of printed parts during printing and prevented shape distortion. Complex solid and porous ceramic structures with a smooth surface and sharp features are fabricated under the optimized parameters. This work provides a new method for the AM of ceramics at µm/mm scale with high surface quality and large geometry variety in an efficient way, opening the possibility for applications in fields such as micromechanical systems and microelectronic components.},
keywords = {Additive Manufacturing, Polymer-derived ceramics},
pubstate = {published},
tppubtype = {article}
}
Additive manufacturing (AM) of ceramics has significantly contributed to advancements in ceramic fabrication, solving some of the difficulties of conventional ceramic processing and providing additional possibilities for the structure and function of components. However, defects induced by the layer‐by‐layer approach on which traditional AM techniques are based still constitute a challenge to address. This study presents the volumetric AM of a SiOC ceramic from a preceramic polymer using xolography, a linear volumetric AM process that allows to avoid the staircase effect typical of other vat photopolymerization techniques. Besides optimizing the trade‐off between preceramic polymer content and transmittance, a pore generator is introduced to create transient channels for gas release before decomposition of the organic constituents and moieties, resulting in crack‐free solid ceramic structures even at low ceramic yield. Formulation optimization alleviated sinking of printed parts during printing and prevented shape distortion. Complex solid and porous ceramic structures with a smooth surface and sharp features are fabricated under the optimized parameters. This work provides a new method for the AM of ceramics at µm/mm scale with high surface quality and large geometry variety in an efficient way, opening the possibility for applications in fields such as micromechanical systems and microelectronic components.
E. Cepollaro; S. Cimino; M. D'Agostini; N. Gargiulo; G. Franchin; L. Lisi
3D-Printed Monoliths Based on Cu-Exchanged SSZ-13 as Catalyst for SCR of NOx Journal Article
In: Catalysts, vol. 14, iss. 1, no. 85, 2024.
Abstract | Links | BibTeX | Tags: Additive Manufacturing, Materials for the environment
@article{nokey,
title = {3D-Printed Monoliths Based on Cu-Exchanged SSZ-13 as Catalyst for SCR of NOx},
author = {E. Cepollaro and S. Cimino and M. D'Agostini and N. Gargiulo and G. Franchin and L. Lisi},
doi = {10.3390/catal14010085},
year = {2024},
date = {2024-01-19},
urldate = {2024-01-19},
journal = {Catalysts},
volume = {14},
number = {85},
issue = {1},
abstract = {Monoliths manufactured by Direct Ink Writing containing 60% SSZ-13 (SiO2/Al2O3 = 23) and SiO2 with 10% laponite as a binder were investigated as self-standing structured catalysts for NH3-SCR of NOx after a short (4 h) and prolonged (24 h) ion exchange with copper and then compared with pure SSZ-13 exchanged under the same conditions. The catalysts were characterized by morphological (XRD and SEM), textural (BET and pore size distribution), chemical (ICP-MS), red-ox (H2-TPR), and surface (NH3-TPD) analyses. The silica-based binder uniformly covered the SSZ-13 particles, and copper was uniformly distributed as well. The main features of the pure Cu-exchanged SSZ-13 zeolite were preserved in the composite monoliths with a negligible contribution of the binder fraction. NH3-SCR tests, carried out on both monolithic and powdered samples in the temperature range of 70–550 °C, showed that composite monoliths provided very good activity, and that the intrinsic activity of SSZ-13 was enhanced by the hierarchical structure of the composite material.},
keywords = {Additive Manufacturing, Materials for the environment},
pubstate = {published},
tppubtype = {article}
}
Monoliths manufactured by Direct Ink Writing containing 60% SSZ-13 (SiO2/Al2O3 = 23) and SiO2 with 10% laponite as a binder were investigated as self-standing structured catalysts for NH3-SCR of NOx after a short (4 h) and prolonged (24 h) ion exchange with copper and then compared with pure SSZ-13 exchanged under the same conditions. The catalysts were characterized by morphological (XRD and SEM), textural (BET and pore size distribution), chemical (ICP-MS), red-ox (H2-TPR), and surface (NH3-TPD) analyses. The silica-based binder uniformly covered the SSZ-13 particles, and copper was uniformly distributed as well. The main features of the pure Cu-exchanged SSZ-13 zeolite were preserved in the composite monoliths with a negligible contribution of the binder fraction. NH3-SCR tests, carried out on both monolithic and powdered samples in the temperature range of 70–550 °C, showed that composite monoliths provided very good activity, and that the intrinsic activity of SSZ-13 was enhanced by the hierarchical structure of the composite material.
K. Huang; A. De Marzi; G. Franchin; P. Colombo
UV-assisted Robotic Arm Freeforming of SiOC Ceramics from a Preceramic Polymer Journal Article
In: Additive Manufacturing, pp. 104051, 2024, ISSN: 2214-8604.
Abstract | Links | BibTeX | Tags: Additive Manufacturing, Polymer-derived ceramics
@article{HUANG2024104051,
title = {UV-assisted Robotic Arm Freeforming of SiOC Ceramics from a Preceramic Polymer},
author = {K. Huang and A. De Marzi and G. Franchin and P. Colombo},
url = {https://www.sciencedirect.com/science/article/pii/S2214860424000976},
doi = {https://doi.org/10.1016/j.addma.2024.104051},
issn = {2214-8604},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-01},
journal = {Additive Manufacturing},
pages = {104051},
abstract = {Material extrusion is a very common and facile additive manufacturing technique for ceramic materials, allowing for rapid design and fabrication of 3D structures without expensive tools. However, fabricating sophisticated structures with large spanning parts and overhanging features using this technology is still a challenge. Here, UV-assisted additive manufacturing is enabled by performing material extrusion with the assistance of UV light using mixture of a preceramic polymer and a photopolymer. The rheological properties of the ink were investigated under UV light radiation to optimize the printing parameters to achieve excellent printability. Complex ceramic structures were fabricated with this method, such as spiral and truss structures, which would be very difficult to obtain using traditional material extrusion without sacrificial supports. These structures have potential application in lightweight ceramic components, such as sandwich structures.},
keywords = {Additive Manufacturing, Polymer-derived ceramics},
pubstate = {published},
tppubtype = {article}
}
Material extrusion is a very common and facile additive manufacturing technique for ceramic materials, allowing for rapid design and fabrication of 3D structures without expensive tools. However, fabricating sophisticated structures with large spanning parts and overhanging features using this technology is still a challenge. Here, UV-assisted additive manufacturing is enabled by performing material extrusion with the assistance of UV light using mixture of a preceramic polymer and a photopolymer. The rheological properties of the ink were investigated under UV light radiation to optimize the printing parameters to achieve excellent printability. Complex ceramic structures were fabricated with this method, such as spiral and truss structures, which would be very difficult to obtain using traditional material extrusion without sacrificial supports. These structures have potential application in lightweight ceramic components, such as sandwich structures.
S. Bhandari; P. Veteška; G. Vajpayee; M. Hinterstein; Ľ. Bača; Z. Hajdúchová; Z. Špitalský; G. Franchin; M. Janek
Material-extrusion based additive manufacturing of BaTiO3 ceramics: from filament production to sintered properties Journal Article
In: Additive Manufacturing, pp. 104238, 2024, ISSN: 2214-8604.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{BHANDARI2024104238,
title = {Material-extrusion based additive manufacturing of BaTiO3 ceramics: from filament production to sintered properties},
author = {S. Bhandari and P. Veteška and G. Vajpayee and M. Hinterstein and Ľ. Bača and Z. Hajdúchová and Z. Špitalský and G. Franchin and M. Janek},
url = {https://www.sciencedirect.com/science/article/pii/S2214860424002847},
doi = {https://doi.org/10.1016/j.addma.2024.104238},
issn = {2214-8604},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-01},
journal = {Additive Manufacturing},
pages = {104238},
abstract = {Material extrusion (MEX) of thermoplastic filaments represents one of the most widely adopted additive manufacturing (AM) technologies. Unlike vat photopolymerization and powder-bed fusion methods that require high energy sources such as UV light and lasers, this fabrication method can be adapted for the fabrication of ceramics by using ceramic loaded filaments as feedstock, yet still employing relatively cheap equipment meant for polymeric materials with little adaptation of the process parameters; this potentially enables a broader diffusion of AM ceramic components. In this work, composite filaments with various weight fractions (60 – 80wt.%) of BaTiO3 were fabricated and characterized by electron microscopy, compressive mechanical testing, rheometry and thermogravimetric analysis to ensure a smooth and reliable printing process. After optimizing the printing parameters, the dense and porous printed samples were carefully debinded and sintered to obtain dense (~ 92%) and defect-free ceramic bodies. The sintered samples were characterized for phase development, microstructure, and pore size distribution. Careful observations reveal a particular range of pore size (0.1 – 5µm), which originates from the binder burn out process. The dielectric and ferroelectric properties of the fabricated samples were in good agreement with those reported in previous literature. This work provides a foundation for rapid prototyping of functional electro ceramics into reliable products with desired functional properties.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Material extrusion (MEX) of thermoplastic filaments represents one of the most widely adopted additive manufacturing (AM) technologies. Unlike vat photopolymerization and powder-bed fusion methods that require high energy sources such as UV light and lasers, this fabrication method can be adapted for the fabrication of ceramics by using ceramic loaded filaments as feedstock, yet still employing relatively cheap equipment meant for polymeric materials with little adaptation of the process parameters; this potentially enables a broader diffusion of AM ceramic components. In this work, composite filaments with various weight fractions (60 – 80wt.%) of BaTiO3 were fabricated and characterized by electron microscopy, compressive mechanical testing, rheometry and thermogravimetric analysis to ensure a smooth and reliable printing process. After optimizing the printing parameters, the dense and porous printed samples were carefully debinded and sintered to obtain dense (~ 92%) and defect-free ceramic bodies. The sintered samples were characterized for phase development, microstructure, and pore size distribution. Careful observations reveal a particular range of pore size (0.1 – 5µm), which originates from the binder burn out process. The dielectric and ferroelectric properties of the fabricated samples were in good agreement with those reported in previous literature. This work provides a foundation for rapid prototyping of functional electro ceramics into reliable products with desired functional properties.
L. Biasetto; V. Gastaldi; H. Elsayed
Co-extrusion of highly loaded feedstocks for fabrication of stainless steel-bioceramic core-shell structures Journal Article
In: Journal of Materials Research and Technology, vol. 33, pp. 6820-6830, 2024, ISSN: 2238-7854.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{BIASETTO20246820,
title = {Co-extrusion of highly loaded feedstocks for fabrication of stainless steel-bioceramic core-shell structures},
author = {L. Biasetto and V. Gastaldi and H. Elsayed},
url = {https://www.sciencedirect.com/science/article/pii/S2238785424025250},
doi = {https://doi.org/10.1016/j.jmrt.2024.10.255},
issn = {2238-7854},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-01},
journal = {Journal of Materials Research and Technology},
volume = {33},
pages = {6820-6830},
abstract = {Co-extrusion of multi-materials structures shows technological challenges and opportunities. Filaments made of a metallic core and a ceramic shell are one example of how structural and functional features can be combined in a single component to provide a synergic effect. In this work, we focused on the fabrication of shell and core-shell scaffolds for potential applications as bone substitutes. Stainless steel 316L was selected for the core material, whilst in situ synthesized sphene (CaTiSiO5) bioactive ceramic was selected as a shell. The combination of a ductile core and a bioactive ceramic, so as scaffolds made of empty struts may represent a new generation of bone substitutes with mechanical properties closer to the ones of natural bone so as with improved bioactivity. Therefore, formulated inks were co-extruded in one step using a customized printing set-up. Microstructural and mechanical properties were investigated on shell and core-shell filaments and 3D structures. Shell bioceramics scaffolds possessed high porosity and target compression strength values. The sintering environment at the core-shell interface caused severe 316L oxidation thus compromising the ductility of the metallic part, however compression strength increased of 53% compared to shell structures.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
Co-extrusion of multi-materials structures shows technological challenges and opportunities. Filaments made of a metallic core and a ceramic shell are one example of how structural and functional features can be combined in a single component to provide a synergic effect. In this work, we focused on the fabrication of shell and core-shell scaffolds for potential applications as bone substitutes. Stainless steel 316L was selected for the core material, whilst in situ synthesized sphene (CaTiSiO5) bioactive ceramic was selected as a shell. The combination of a ductile core and a bioactive ceramic, so as scaffolds made of empty struts may represent a new generation of bone substitutes with mechanical properties closer to the ones of natural bone so as with improved bioactivity. Therefore, formulated inks were co-extruded in one step using a customized printing set-up. Microstructural and mechanical properties were investigated on shell and core-shell filaments and 3D structures. Shell bioceramics scaffolds possessed high porosity and target compression strength values. The sintering environment at the core-shell interface caused severe 316L oxidation thus compromising the ductility of the metallic part, however compression strength increased of 53% compared to shell structures.
V. Diamanti; H. Elsayed; E. Bernardo
Hybrid direct ink writing of bioglass-calcite-carbon composite scaffolds supported by novel silicone-based emulsions Journal Article
In: Ceramics International, vol. 50, no. 24, Part B, pp. 53646-53654, 2024, ISSN: 0272-8842.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{DIAMANTI202453646,
title = {Hybrid direct ink writing of bioglass-calcite-carbon composite scaffolds supported by novel silicone-based emulsions},
author = {V. Diamanti and H. Elsayed and E. Bernardo},
url = {https://www.sciencedirect.com/science/article/pii/S0272884224047369},
doi = {https://doi.org/10.1016/j.ceramint.2024.10.215},
issn = {0272-8842},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-01},
journal = {Ceramics International},
volume = {50},
number = {24, Part B},
pages = {53646-53654},
abstract = {70S30C (70 mol% SiO2, 30 % CaO) bioglass is one of the most promising bioceramics for bone tissue engineering. We discuss the feasibility of 70S30C bioglass/calcite/carbon composites derived from novel silicone-based emulsions, leading to highly porous lattice scaffolds. These are produced by direct ink writing (DIW) 3D printing, followed by ceramic conversion at 700 °C in flowing nitrogen. The emulsions consisted of droplets of concentrated calcium nitrate aqueous solution incorporated into blends of H44 commercial polysiloxane and photocurable acrylate resin. This formulation offered unprecedented opportunities in both synthesis and shaping. Specifically, the homogeneous dispersion of the CaO precursor in silicone enabled a uniform SiO2/CaO distribution, favoring the formation of a glass matrix. Additionally, the acrylate component and water content allowed for tuning of the microstructure both immediately after printing and upon firing. Photopolymerization of acrylates consolidated the printed bodies (configuring a ‘hybrid DIW’) after extrusion, while water evaporation enhanced gas evolution during ceramic conversion, promoting pore interconnectivity.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
70S30C (70 mol% SiO2, 30 % CaO) bioglass is one of the most promising bioceramics for bone tissue engineering. We discuss the feasibility of 70S30C bioglass/calcite/carbon composites derived from novel silicone-based emulsions, leading to highly porous lattice scaffolds. These are produced by direct ink writing (DIW) 3D printing, followed by ceramic conversion at 700 °C in flowing nitrogen. The emulsions consisted of droplets of concentrated calcium nitrate aqueous solution incorporated into blends of H44 commercial polysiloxane and photocurable acrylate resin. This formulation offered unprecedented opportunities in both synthesis and shaping. Specifically, the homogeneous dispersion of the CaO precursor in silicone enabled a uniform SiO2/CaO distribution, favoring the formation of a glass matrix. Additionally, the acrylate component and water content allowed for tuning of the microstructure both immediately after printing and upon firing. Photopolymerization of acrylates consolidated the printed bodies (configuring a ‘hybrid DIW’) after extrusion, while water evaporation enhanced gas evolution during ceramic conversion, promoting pore interconnectivity.
2023
L. Biasetto; A. Gleadall; V. Gastaldi
Ink Tuning for Direct Ink Writing of Planar Metallic Lattices Journal Article
In: Adv Eng Mater, vol. 25, no. 20, 2023, ISSN: 1527-2648.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{Biasetto2023,
title = {Ink Tuning for Direct Ink Writing of Planar Metallic Lattices},
author = {L. Biasetto and A. Gleadall and V. Gastaldi},
doi = {10.1002/adem.202201858},
issn = {1527-2648},
year = {2023},
date = {2023-10-00},
urldate = {2023-10-00},
journal = {Adv Eng Mater},
volume = {25},
number = {20},
publisher = {Wiley},
abstract = {316L and Cu‐based inks are developed to 3D‐printed tetrachiral auxetic structures. The main objectives of the work are to study the effects of powders composition and powder:binder volume ratio on rheological properties and printability of the inks. Following these results, customized Gcode is developed using FullControl Gcode Designer open‐source software to 3D print intricate tetrachiral auxetic structures. The results reported in this work show how powder composition (316L versus Cu) has less effect on the inks’ rheological behavior than powder size distribution and powders:binder volume ratio. In terms of rheological parameters, the zero‐shear rate viscosity mainly affects the capability of the printed ink to retain its shape after printing, while the yield stress affects the printability. The printed and sintered auxetic structures achieve the intended lattice‐geometry design.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
316L and Cu‐based inks are developed to 3D‐printed tetrachiral auxetic structures. The main objectives of the work are to study the effects of powders composition and powder:binder volume ratio on rheological properties and printability of the inks. Following these results, customized Gcode is developed using FullControl Gcode Designer open‐source software to 3D print intricate tetrachiral auxetic structures. The results reported in this work show how powder composition (316L versus Cu) has less effect on the inks’ rheological behavior than powder size distribution and powders:binder volume ratio. In terms of rheological parameters, the zero‐shear rate viscosity mainly affects the capability of the printed ink to retain its shape after printing, while the yield stress affects the printability. The printed and sintered auxetic structures achieve the intended lattice‐geometry design.
S. Bhandari; C. Maniere; F. Sedona; E. De Bona; V. M. Sglavo; P. Colombo; L. Fambri; M. Biesuz; G. Franchin
Ultra-rapid debinding and sintering of additively manufactured ceramics by ultrafast high-temperature sintering Journal Article
In: Journal of the European Ceramic Society, 2023, ISSN: 0955-2219.
Abstract | Links | BibTeX | Tags: Additive Manufacturing
@article{BHANDARI2023,
title = {Ultra-rapid debinding and sintering of additively manufactured ceramics by ultrafast high-temperature sintering},
author = {S. Bhandari and C. Maniere and F. Sedona and E. De Bona and V. M. Sglavo and P. Colombo and L. Fambri and M. Biesuz and G. Franchin},
url = {https://www.sciencedirect.com/science/article/pii/S0955221923006660},
doi = {https://doi.org/10.1016/j.jeurceramsoc.2023.08.040},
issn = {0955-2219},
year = {2023},
date = {2023-08-25},
urldate = {2023-01-01},
journal = {Journal of the European Ceramic Society},
abstract = {In recent years, additive manufacturing (AM) of ceramics has significantly advanced in terms of the range of equipment available, printing resolution and productivity. Most techniques involve the use of ceramic powders embedded in an organic binder which is typically removed through a slow thermal debinding process. Herein, we prove for the first time that ultra-rapid debinding and sintering are possible for complex 3YSZ components produced using material extrusion technology. The printed components were first chemically debinded in acetone thus removing about one-half of the binder, and then thermally debinded and sintered by ultrafast high-temperature sintering (UHS) in a single-step process (30 to 120s). Fully dense components were obtained with tailored microstructure and nanometric grain size. The sintered artefacts were crack-free even at the microscopic level. This approach paves the way for rapid processing (debinding and sintering) of additively manufactured ceramics with reduced energy consumption and carbon footprint.},
keywords = {Additive Manufacturing},
pubstate = {published},
tppubtype = {article}
}
In recent years, additive manufacturing (AM) of ceramics has significantly advanced in terms of the range of equipment available, printing resolution and productivity. Most techniques involve the use of ceramic powders embedded in an organic binder which is typically removed through a slow thermal debinding process. Herein, we prove for the first time that ultra-rapid debinding and sintering are possible for complex 3YSZ components produced using material extrusion technology. The printed components were first chemically debinded in acetone thus removing about one-half of the binder, and then thermally debinded and sintered by ultrafast high-temperature sintering (UHS) in a single-step process (30 to 120s). Fully dense components were obtained with tailored microstructure and nanometric grain size. The sintered artefacts were crack-free even at the microscopic level. This approach paves the way for rapid processing (debinding and sintering) of additively manufactured ceramics with reduced energy consumption and carbon footprint.