Ultra-High Early Strength Cementitious Grout Suitable for Additive Manufacturing Applications Fabricated by Using Graphene Oxide and Viscosity Modifying Agents

One of the considerable challenges in the design of cementitious mixtures for additive manufacturing/three-dimensional (3D) printing applications is achieving both suitable fresh properties and significant mechanical strengths. This paper presents the use of graphene oxide (GO) as a promising nano reinforcement material with the potential to improve the printing feasibility and quality of a 3D printed cementitious matrix. Additionally, in this study, a viscosity modifying agent (VMA) was employed as a chemical additive to attain the required consistency and flow. The printed mixture was fabricated using various cementitious materials and waste materials. This study investigated the impact of GO and VMA on the enhancement of the 3D printing of cementitious composites through several tests. A flow test was conducted using the flow table test. The results showed a high fluidity and practical consistency, which are essential for nozzle pumping and accurateness in printed shapes. Furthermore, the bleeding test showed minimal bleeding up to hardening, and a considerable self-cleaning ability was noted during handling when conducting examinations of fresh properties. For hardened properties, the mechanical strengths were exceptionally high, especially at early ages, which is crucial for the stability of sequence layers of printed composites. The tensile strengths were 3.77, 10.5, 13.35, and 18.83 MPa at 1, 3, 7, and 28 days, respectively, and the compressive strengths were 25.1, 68.4, 85.6, and 125.4 MPa at 1, 3, 7, and 28 days, respectively. The test results showed the effectiveness of the fabricated cementitious mixture design method for meeting the requirements for 3D concrete printing applications.

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Multi-resolution in architecture as a design driver for additive manufacturing applications

International Journal of Architectural Computing ◽

10.1177/1478077120924802 ◽

2020 ◽

Vol 18 (3) ◽

pp. 218-234

Author(s):

Manuel Ladron de Guevara ◽

Luis Ricardo Borunda ◽

Daragh Byrne ◽

Ramesh Krishnamurti

Keyword(s):

Additive Manufacturing ◽

Computational Methods ◽

Computational Models ◽

Three Dimensional ◽

Discrete Models ◽

Computational Power ◽

Manufacturing Applications ◽

The Impact

Additive manufacturing is evolving toward more sophisticated territory for architects and designers, mainly through the increased use of scripting tools. Recognizing this, we present a design and fabrication pipeline comprised of a class of techniques for fabrication and methods of design through discrete computational models. These support a process responsive to varied design intents: this structured workflow expands the design and fabrication space of any input shape, without having to explicitly deal with the complexity of discrete models beforehand. We discuss a multi-resolution-based methodology that incorporates discrete computational methods, spatial additive manufacturing with both robotic and commercial three-dimensional printers, as well as, a free-oriented technique. Finally, we explore the impact of computational power on design outcome, examining in-depth the concept of resolution as a design driver.

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Efficient 3D printing via photooxidation of ketocoumarin based photopolymerization

Nature Communications ◽

10.1038/s41467-021-23170-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xiaoyu Zhao ◽

Ye Zhao ◽

Ming-De Li ◽

Zhong’an Li ◽

Haiyan Peng ◽

...

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Visible Light ◽

Light Exposure ◽

Three Dimensional ◽

3D Printer ◽

Light Penetration ◽

Viable Solution

AbstractPhotopolymerization-based three-dimensional (3D) printing can enable customized manufacturing that is difficult to achieve through other traditional means. Nevertheless, it remains challenging to achieve efficient 3D printing due to the compromise between print speed and resolution. Herein, we report an efficient 3D printing approach based on the photooxidation of ketocoumarin that functions as the photosensitizer during photopolymerization, which can simultaneously deliver high print speed (5.1 cm h−1) and high print resolution (23 μm) on a common 3D printer. Mechanistically, the initiating radical and deethylated ketocoumarin are both generated upon visible light exposure, with the former giving rise to rapid photopolymerization and high print speed while the latter ensuring high print resolution by confining the light penetration. By comparison, the printed feature is hard to identify when the ketocoumarin encounters photoreduction due to the increased lateral photopolymerization. The proposed approach here provides a viable solution towards efficient additive manufacturing by controlling the photoreaction of photosensitizers during photopolymerization.

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An Overview on the Rheology, Mechanical Properties, Durability, 3D Printing, and Microstructural Performance of Nanomaterials in Cementitious Composites

Materials ◽

10.3390/ma14112950 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2950

Author(s):

Hongwei Song ◽

Xinle Li

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Three Dimensional ◽

Cementitious Materials ◽

Research Area ◽

Cementitious Composites ◽

Split Tensile Strength ◽

Contour Crafting ◽

Wide Range ◽

Active Research

The most active research area is nanotechnology in cementitious composites, which has a wide range of applications and has achieved popularity over the last three decades. Nanoparticles (NPs) have emerged as possible materials to be used in the field of civil engineering. Previous research has concentrated on evaluating the effect of different NPs in cementitious materials to alter material characteristics. In order to provide a broad understanding of how nanomaterials (NMs) can be used, this paper critically evaluates previous research on the influence of rheology, mechanical properties, durability, 3D printing, and microstructural performance on cementitious materials. The flow properties of fresh cementitious composites can be measured using rheology and slump. Mechanical properties such as compressive, flexural, and split tensile strength reveal hardened properties. The necessary tests for determining a NM’s durability in concrete are shrinkage, pore structure and porosity, and permeability. The advent of modern 3D printing technologies is suitable for structural printing, such as contour crafting and binder jetting. Three-dimensional (3D) printing has opened up new avenues for the building and construction industry to become more digital. Regardless of the material science, a range of problems must be tackled, including developing smart cementitious composites suitable for 3D structural printing. According to the scanning electron microscopy results, the addition of NMs to cementitious materials results in a denser and improved microstructure with more hydration products. This paper provides valuable information and details about the rheology, mechanical properties, durability, 3D printing, and microstructural performance of cementitious materials with NMs and encourages further research.

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

3D Printing in Medicine ◽

10.1186/s41205-021-00098-5 ◽

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.

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3D Technology – Additive Manufacturing Applications and Prospects (Vol. 24, No. 9, Full Issue)

Asia-Pacific Biotech News ◽

10.1142/s0219030320001093 ◽

2020 ◽

Vol 24 (09) ◽

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Environmental Impact ◽

Real World ◽

Vaccine Development ◽

Health Screening ◽

Wide Range ◽

The World ◽

Real World Applications ◽

Manufacturing Applications

For the month of September 2020, APBN dives into the world of 3D printing and its wide range of real-world applications. Keeping our focus on the topic of the year, the COVID-19 pandemic, we explore the environmental impact of the global outbreak as well as gain insight to the top 5 vaccine platforms used in vaccine development. Discover more about technological advancements and how it is assisting innovation in geriatric health screening.

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Advances in 3D Printing for Tissue Engineering

Materials ◽

10.3390/ma14123149 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3149

Author(s):

Angelika Zaszczyńska ◽

Maryla Moczulska-Heljak ◽

Arkadiusz Gradys ◽

Paweł Sajkiewicz

Keyword(s):

Tissue Engineering ◽

Additive Manufacturing ◽

3D Printing ◽

Complex Structure ◽

Three Dimensional ◽

Computer Assisted ◽

Scaffold Fabrication ◽

Manufacturing Techniques ◽

Printing Techniques ◽

State Of Art

Tissue engineering (TE) scaffolds have enormous significance for the possibility of regeneration of complex tissue structures or even whole organs. Three-dimensional (3D) printing techniques allow fabricating TE scaffolds, having an extremely complex structure, in a repeatable and precise manner. Moreover, they enable the easy application of computer-assisted methods to TE scaffold design. The latest additive manufacturing techniques open up opportunities not otherwise available. This study aimed to summarize the state-of-art field of 3D printing techniques in applications for tissue engineering with a focus on the latest advancements. The following topics are discussed: systematics of the available 3D printing techniques applied for TE scaffold fabrication; overview of 3D printable biomaterials and advancements in 3D-printing-assisted tissue engineering.

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Algorithm to Reduce Leading and Lagging in Conformal Direct-Print

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4040730 ◽

2018 ◽

Vol 140 (10) ◽

Cited By ~ 2

Author(s):

Morteza Vatani ◽

Faez Alkadi ◽

Jae-Won Choi

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

3D Model ◽

Three Dimensional ◽

Motion Direction ◽

B Spline ◽

And Topology ◽

Printing System ◽

3D Printed ◽

Printed Patterns

A novel additive manufacturing algorithm was developed to increase the consistency of three-dimensional (3D) printed curvilinear or conformal patterns on freeform surfaces. The algorithm dynamically and locally compensates the nozzle location with respect to the pattern geometry, motion direction, and topology of the substrate to minimize lagging or leading during conformal printing. The printing algorithm was implemented in an existing 3D printing system that consists of an extrusion-based dispensing module and an XYZ-stage. A dispensing head is fixed on a Z-axis and moves vertically, while the substrate is installed on an XY-stage and moves in the x–y plane. The printing algorithm approximates the printed pattern using nonuniform rational B-spline (NURBS) curves translated directly from a 3D model. Results showed that the proposed printing algorithm increases the consistency in the width of the printed patterns. It is envisioned that the proposed algorithm can facilitate nonplanar 3D printing using common and commercially available Cartesian-type 3D printing systems.

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Additive Manufacturing of Biopolymers for Tissue Engineering and Regenerative Medicine: An Overview, Potential Applications, Advancements, and Trends

International Journal of Polymer Science ◽

10.1155/2021/4907027 ◽

2021 ◽

Vol 2021 ◽

pp. 1-20 ◽

Cited By ~ 2

Author(s):

Dhinakaran Veeman ◽

M. Swapna Sai ◽

P. Sureshkumar ◽

T. Jagadeesha ◽

L. Natrayan ◽

...

Keyword(s):

Tissue Engineering ◽

Additive Manufacturing ◽

3D Printing ◽

Regenerative Medicine ◽

Tissue Regeneration ◽

Three Dimensional ◽

Porous Scaffolds ◽

Wide Range ◽

Potential Applications ◽

Pharmaceutical Industries

As a technique of producing fabric engineering scaffolds, three-dimensional (3D) printing has tremendous possibilities. 3D printing applications are restricted to a wide range of biomaterials in the field of regenerative medicine and tissue engineering. Due to their biocompatibility, bioactiveness, and biodegradability, biopolymers such as collagen, alginate, silk fibroin, chitosan, alginate, cellulose, and starch are used in a variety of fields, including the food, biomedical, regeneration, agriculture, packaging, and pharmaceutical industries. The benefits of producing 3D-printed scaffolds are many, including the capacity to produce complicated geometries, porosity, and multicell coculture and to take growth factors into account. In particular, the additional production of biopolymers offers new options to produce 3D structures and materials with specialised patterns and properties. In the realm of tissue engineering and regenerative medicine (TERM), important progress has been accomplished; now, several state-of-the-art techniques are used to produce porous scaffolds for organ or tissue regeneration to be suited for tissue technology. Natural biopolymeric materials are often better suited for designing and manufacturing healing equipment than temporary implants and tissue regeneration materials owing to its appropriate properties and biocompatibility. The review focuses on the additive manufacturing of biopolymers with significant changes, advancements, trends, and developments in regenerative medicine and tissue engineering with potential applications.

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Modelling, Design and Validation of a Parallel Kinematic Robot for Additive Manufacture Applications

10.17352/ara.000009 ◽

2021 ◽

pp. 019-029

Author(s):

Lahoud Marcel ◽

Melendez Leonardo ◽

Gil Arturo

Keyword(s):

Additive Manufacturing ◽

Open Source Software ◽

Design Method ◽

Kinematic Model ◽

Additive Manufacture ◽

Parallel Kinematics ◽

Cartesian Space ◽

Parallel Kinematic ◽

Manufacturing Applications ◽

Design Construction

The additive manufacture is a fabrication process that has taken huge steps in the last decade, even though the first researches and prototypes are around since almost forty years ago. In this article, a design method for a Parallel Kinematics Robot for Additive Manufacturing Applications is proposed. A numerical model is obtained from the kinematics of the robot for which the design, construction and assembly are planned using recycled materials and equipment. The control of the robot is done using open source software, allowing the planning of trajectories in the Cartesian space on a maximum designed cylindrical workspace of 300mm in diameter by 300mm high. At the end of the work the robot was identified, the kinematic model was validated and considerations for future works were given.

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Transfiguring Healthcare: Three-Dimensional Printing in Pharmaceutical Sciences; Trends during COVID-19: A Review

Journal of Pharmaceutical Research International ◽

10.9734/jpri/2021/v33i56b33946 ◽

2021 ◽

pp. 207-218

Author(s):

K. G. Siree ◽

T. M. Amulya ◽

T. M. Pramod Kumar ◽

S. Sowmya ◽

K. Divith ◽

...

Keyword(s):

3D Printing ◽

Medical Devices ◽

Three Dimensional ◽

Pharmaceutical Sciences ◽

Three Dimensional Printing ◽

Custom Made ◽

High Degree ◽

The Impact ◽

Dimensional Printing ◽

Shed Light

Three-dimensional (3D) printing is a unique technique that allows for a high degree of customisation in pharmacy, dentistry and in designing of medical devices. 3D printing satiates the increasing exigency for consumer personalisation in these fields as custom-made medicines catering to the patients’ requirements are novel advancements in drug therapy. Current research in 3D printing indicates towards reproducing an organ in the form of a chip; paving the way for more studies and opportunities to perfecting the existing technique. In addition, we will also attempt to shed light on the impact of 3D printing in the COVID-19 pandemic.

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