scholarly journals Extrusion-Based 3D Printing of Ceramic Pastes: Mathematical Modeling and In Situ Shaping Retention Approach

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1137
Author(s):  
Fuwen Hu ◽  
Tadeusz Mikolajczyk ◽  
Danil Yurievich Pimenov ◽  
Munish Kumar Gupta
Keyword(s):  
3D Printing ◽  
Digital Control ◽  
Digital Fabrication ◽  
Industrial Applications ◽  
Drying Kinetics ◽  
Ease Of Use ◽  
Layer By Layer ◽  
Thin Wall ◽  
Shape Retention

Extrusion-based three-dimensional (3D) printing methods are preferred and emerging approaches for freely digital fabrication of ceramics due to ease of use, low investment, high utilization of materials, and good adaptability to multi-materials. However, systematic knowledge still lacks an explanation for what is their 3D printability. Moreover, some uncontrollable factors including extrudate shape retention and nonuniform drying inevitably limit their industrial applications. The purpose of this research was to present a new shaping retention method based on mathematical synthesis modeling for extrusion-based 3D-printing of ceramic pastes. Firstly, the steady-state equilibrium equation of the extrusion process was derived to provide clearer theoretical indications than purely experimental methods. Furthermore, a mathematical description framework was synthesized to better understand the extrusion-based 3D-printing of ceramic pastes from several realms: pastes rheology, extrudability, shape-holdability, and drying kinetics. Secondly, for eliminating shaping drawbacks (e.g., deformation and cracks) originating from non-digital control factors, we put forward a digital shape-retention technology inspired by the generalized drying kinetics of porous materials, which was different from existing retention solutions, e.g., freezing retention, thermally induced gelation, and using removable support structures. In addition, we developed an in situ hot air flow drying device easily attached to the nozzle of existing 3D printers. Confirmatory 3D-printing experiments of thin-walled cone-shape benchmark parts and the fire arrowhead-like object clearly demonstrated that the presented shape-retention method not only upgraded layer-by-layer forming capability but also enabled digital control of extrudate solidification. In addition, many more experimental results statistically showed that both fully solid parts and purely thin-wall parts had higher dimensional accuracy and better surface quality than the offline drying method. The 3D printed ceramic products with complex profiled surfaces conceivably demonstrated that our improved extrusion-based 3D-printing process of ceramic pastes has game-changing potentials beyond the traditional craftsmanship capacity.

Continuous Liquid Interface Production of 3D Objects: An Unconventional Technology and its Challenges and Opportunities

2017 ◽  
Author(s):  
Judah Balli ◽  
Subha Kumpaty ◽  
Vince Anewenter
Keyword(s):  
3D Printing ◽  
Industrial Applications ◽  
Research Literature ◽  
Liquid Interface ◽  
Layer By Layer ◽  
Support Structure ◽  
Practical Applications ◽  
3D Objects ◽  
Continuous Liquid Interface Production ◽  
Part Orientation

The purpose of this paper is to understand and research literature on the “continuous liquid interface production (CLIP)” of 3D objects to address the current challenges. This proprietary technology was originally owned by EiPi Systems but is now being developed by Carbon 3D. Unlike conventional rapid prototyping of printing layer-by-layer to print 3D objects, CLIP is achieved with an oxygen-permeable window made of proprietary glass membrane and the ultraviolet image projection plane below it, which allows the continuous liquid interface to produce 3D objects where photo-polymerization is restricted between the window and the polymerizing part. This process eliminates the time requirement in between the layers resulting in the faster production of 3D objects with a resolution less than 100 microns. It is a known factor that the “supports” play a vital role in any liquid based 3D printing techniques and this does not change in CLIP. In addition to the parameters of support structure like shape, size, strength, ease of removability, surface finish after removal of supports etc, CLIP needs to deal with different types of materials. The support structure needs to be designed according to the respective material’s properties. There are two broad categories of the materials available from Carbon 3D, prototyping resins, and engineering resins. While the prototyping resin is used for the cosmetic models and the engineering resins are used for the practical applications. There are 6 types of engineering resins developed for the end user; of these, EPU and CE are more challenging to work with. EPU parts needs more supports and careful handling till the completion of post processing as the material is soft. CE parts are fragile and needs more systematic handling to complete the successful production. Although printing parts of EPU and CE is more time consuming when compared to the normal CLIP process, they are worth for their unmatched industrial applications. None of the existing 3D printing technologies offers this quality. The support structure, orientation and pot life are the influencing parameters for all resins. In this study, it is statistically proven that by optimizing the part orientation with respect to the slicing of each layer and customized supports; parts are built way better than before. The part orientation is optimized by ensuring each layer is supporting the subsequent layer and minimizing the islands. It is noticed that the results are always better by tilting the part 5 to 10 degrees in both X and Y axis in the build setup and this applies for most of the straight geometrical parts. For parts of specific geometry which can create a vacuum while pulling up the part needs to be oriented in a different way or create a re-closable air passage that can prevent the vacuum being created.

Epitaxial growth manner and structure of superconducting oxide films

1990 ◽  
Vol 48 (4) ◽  
pp. 2-3
Author(s):  
Yoshichika Bando ◽  
Takahito Terashima ◽  
Kenji Iijima ◽  
Kazunuki Yamamoto ◽  
Kazuto Hirata ◽  
...  
Keyword(s):  
Ultrathin Films ◽  
Film Surface ◽  
High Energy ◽  
Epitaxial Films ◽  
Layer By Layer ◽  
Initial Growth ◽  
In Situ Growth ◽  
High Quality ◽  
Activated Reactive Evaporation

The high quality thin films of high-Tc superconducting oxide are necessary for elucidating the superconducting mechanism and for device application. The recent trend in the preparation of high-Tc films has been toward “in-situ” growth of the superconducting phase at relatively low temperatures. The purpose of “in-situ” growth is to attain surface smoothness suitable for fabricating film devices but also to obtain high quality film. We present the investigation on the initial growth manner of YBCO by in-situ reflective high energy electron diffraction (RHEED) technique and on the structural and superconducting properties of the resulting ultrathin films below 100Å. The epitaxial films have been grown on (100) plane of MgO and SrTiO, heated below 650°C by activated reactive evaporation. The in-situ RHEED observation and the intensity measurement was carried out during deposition of YBCO on the substrate at 650°C. The deposition rate was 0.8Å/s. Fig. 1 shows the RHEED patterns at every stage of deposition of YBCO on MgO(100). All the patterns exhibit the sharp streaks, indicating that the film surface is atomically smooth and the growth manner is layer-by-layer.

Oblique-incidence Reflectivity Difference (OI-RD) and Leed Studies of Adsorption and Growth of Xe on Nb(110)

2003 ◽  
Vol 780 ◽  
Author(s):  
P. Thomas ◽  
E. Nabighian ◽  
M.C. Bartelt ◽  
C.Y. Fong ◽  
X.D. Zhu
Keyword(s):  
Transition Layer ◽  
Layer Growth ◽  
Flow Mode ◽  
Layer By Layer ◽  
Zeroth Order ◽  
Step Flow ◽  
Low Energy Electron Diffraction ◽  
Oriented Film ◽  
Low Energy Electron

AbstractWe studied adsorption, growth and desorption of Xe on Nb(110) using an in-situ obliqueincidence reflectivity difference (OI-RD) technique and low energy electron diffraction (LEED) from 32 K to 100 K. The results show that Xe grows a (111)-oriented film after a transition layer is formed on Nb(110). The transition layer consists of three layers. The first two layers are disordered with Xe-Xe separation significantly larger than the bulk value. The third monolayer forms a close packed (111) structure on top of the tensile-strained double layer and serves as a template for subsequent homoepitaxy. The adsorption of the first and the second layers are zeroth order with sticking coefficient close to one. Growth of the Xe(111) film on the transition layer proceeds in a step flow mode from 54K to 40K. At 40K, an incomplete layer-by-layer growth is observed while below 35K the growth proceeds in a multilayer mode.

A Strategy for Fabricating in Situ Topographical 3D Scaffolds Using 3D Printing and Pluronic F-127

2019 ◽  
Author(s):  
JiUn Lee ◽  
SooJung Chae ◽  
Hyeongjin Lee ◽  
GeunHyung Kim
Keyword(s):  
3D Printing ◽  
3D Scaffolds

scholarly journals A Review on LDH-Smart Functionalization of Anodic Films of Mg Alloys

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 536
Author(s):  
Mosab Kaseem ◽  
Karna Ramachandraiah ◽  
Shakhawat Hossain ◽  
Burak Dikici
Keyword(s):  
Industrial Applications ◽  
Mg Alloys ◽  
Anodic Films ◽  
Electrolytic Oxidation ◽  
Recent Developments ◽  
Plasma Electrolytic ◽  
Co Precipitation ◽  
Corrosive Environments ◽  
Double Hydroxide

This review presents an overview of the recent developments in the synthesis of layered double hydroxide (LDH) on the anodized films of Mg alloys prepared by either conventional anodizing or plasma electrolytic oxidation (PEO) and the applications of the formed composite ceramics as smart chloride traps in corrosive environments. In this work, the main fabrication approaches including co-precipitation, in situ hydrothermal, and an anion exchange reaction are outlined. The unique structure of LDH nanocontainers enables them to intercalate several corrosion inhibitors and release them when required under the action of corrosion-relevant triggers. The influences of different variables, such as type of cations, the concentration of salts, pH, and temperature, immersion time during the formation of LDH/anodic film composites, on the electrochemical response are also highlighted. The correlation between the dissolution rate of PEO coating and the growth rate of the LDH film was discussed. The challenges and future development strategies of LDH/anodic films are also highlighted in terms of industrial applications of these materials.

scholarly journals Ultrafast Electrohydrodynamic 3D Printing with in situ Jet Speed Monitoring

2021 ◽  
pp. 109791
Author(s):  
Ievgenii Liashenko ◽  
Alberto Ramon ◽  
Andreu Cabot ◽  
Joan Rosell-Llompart
Keyword(s):  
3D Printing

scholarly journals A guideline for 3D printing terminology in biomedical research utilizing ISO/ASTM standards

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Amy E. Alexander ◽  
Nicole Wake ◽  
Leonid Chepelev ◽  
Philipp Brantner ◽  
Justin Ryan ◽  
...  
Keyword(s):  
3D Printing ◽  
Medical Literature ◽  
Three Dimensional ◽  
Physical Object ◽  
Medical Community ◽  
Layer By Layer ◽  
Digital File ◽  
Standardized Terminology ◽  
Standard Terms ◽  
The Impact

AbstractFirst patented in 1986, three-dimensional (3D) printing, also known as additive manufacturing or rapid prototyping, now encompasses a variety of distinct technology types where material is deposited, joined, or solidified layer by layer to create a physical object from a digital file. As 3D printing technologies continue to evolve, and as more manuscripts describing these technologies are published in the medical literature, it is imperative that standardized terminology for 3D printing is utilized. The purpose of this manuscript is to provide recommendations for standardized lexicons for 3D printing technologies described in the medical literature. For all 3D printing methods, standard general ISO/ASTM terms for 3D printing should be utilized. Additional, non-standard terms should be included to facilitate communication and reproducibility when the ISO/ASTM terms are insufficient in describing expository details. By aligning to these guidelines, the use of uniform terms for 3D printing and the associated technologies will lead to improved clarity and reproducibility of published work which will ultimately increase the impact of publications, facilitate quality improvement, and promote the dissemination and adoption of 3D printing in the medical community.

scholarly journals Three-dimensionally printed polycaprolactone/multicomponent bioactive glass scaffolds for potential application in bone tissue engineering

2020 ◽  
Vol 6 (1) ◽  
pp. 57-69
Author(s):  
Amirhosein Fathi ◽  
Farzad Kermani ◽  
Aliasghar Behnamghader ◽  
Sara Banijamali ◽  
Masoud Mozafari ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
3D Printing ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Three Dimensional ◽  
Layer By Layer ◽  
Composite Scaffolds ◽  
3D Printed ◽  
Co Doped

AbstractOver the last years, three-dimensional (3D) printing has been successfully applied to produce suitable substitutes for treating bone defects. In this work, 3D printed composite scaffolds of polycaprolactone (PCL) and strontium (Sr)- and cobalt (Co)-doped multi-component melt-derived bioactive glasses (BGs) were prepared for bone tissue engineering strategies. For this purpose, 30% of as-prepared BG particles (size <38 μm) were incorporated into PCL, and then the obtained composite mix was introduced into a 3D printing machine to fabricate layer-by-layer porous structures with the size of 12 × 12 × 2 mm3.The scaffolds were fully characterized through a series of physico-chemical and biological assays. Adding the BGs to PCL led to an improvement in the compressive strength of the fabricated scaffolds and increased their hydrophilicity. Furthermore, the PCL/BG scaffolds showed apatite-forming ability (i.e., bioactivity behavior) after being immersed in simulated body fluid (SBF). The in vitro cellular examinations revealed the cytocompatibility of the scaffolds and confirmed them as suitable substrates for the adhesion and proliferation of MG-63 osteosarcoma cells. In conclusion, 3D printed composite scaffolds made of PCL and Sr- and Co-doped BGs might be potentially-beneficial bone replacements, and the achieved results motivate further research on these materials.

Sign in / Sign up

Export Citation Format

Share Document