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Special Issue "NextGen Materials for 3D Printing"

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Manufacturing Processes and Systems".

Deadline for manuscript submissions: closed (31 December 2017)

Special Issue Editors

Guest Editor
Prof. Dr. Chee Kai Chua

Singapore Centre for 3D Printing, School of Mechanical & Aerospace Engineering, Nanyang Technological University, N3.1-B2c-03b, 50 Nanyang Avenue, Singapore 639798
Website 1 | Website 2 | E-Mail
Interests: geometric modelling; rapid prototyping; additive manufacturing; 3D printing; reverse engineering; biomedical engineering design; tissue engineering; biomaterials; bioprinting
Guest Editor
Dr. Jia An

Singapore Centre for 3D Printing, School of Mechanical & Aerospace Engineering, Nanyang Technological University, N3.1-B2c-03b, 50 Nanyang Avenue, Singapore 639798
Website | E-Mail
Interests: 3D printing; bioprinting; biomaterials; polymer processing; polymer microfibers; polymer membranes; tissue engineering
Guest Editor
Assist. Prof. Dr. Wai Yee Yeong

Singapore Centre for 3D Printing, School of Mechanical & Aerospace Engineering, Nanyang Technological University, N3.2-02-27, 50 Nanyang Avenue, Singapore 639798
Website 1 | Website 2 | E-Mail
Interests: rapid prototyping; additive manufacturing; tissue engineering, biomaterials; 3D bioprinting; laser-material interaction; medical devices; lightweight structure and design; metal printing; qualification ad certification of AM parts.

Special Issue Information

Dear Colleagues,

3D printing, formally known as additive manufacturing, has advanced significantly in the field of processing materials. Recently, many materials, most deemed as non-printable before, have surfaced in the field of 3D printing as new 3D printable materials; for example, glass, concrete, carbon fibers, dissolvable metals, etc. Though not many have reached commercial maturity, the endless possibilities of 3D printing have been undoubtedly manifested. This causes us to consider, by looking at today’s range of materials and the range of 3D printable materials, what will 3D printing look like tomorrow? This exciting question motivates us to propose a Special Issue on the next generation of 3D printing materials.

The focus of this Special Issue is on new, 3D printable materials. Any topics involving 3D printing materials will be of interest to us. Please refer to the following list of suggested keywords for the scope of this Special Issue. We look forward to your contribution.

Prof. Dr. Chee Kai Chua
Assist. Prof. Dr. Wai Yee Yeong
Dr. Jia An
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Multi-materials
  • Hybrid materials
  • Smart materials (e.g. shape memory materials)
  • Magnetic materials
  • Glass and ceramics
  • Functional materials
  • New biomaterials
  • Nanomaterials/Nanocomposites
  • Cement and concrete
  • Carbon fibre composites
  • Dissolvable metals
  • Drugs/pharmaceuticals
  • Food/nutrients

Published Papers (13 papers)

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Editorial

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Open AccessEditorial Special Issue: NextGen Materials for 3D Printing
Materials 2018, 11(4), 555; https://doi.org/10.3390/ma11040555
Received: 3 April 2018 / Revised: 3 April 2018 / Accepted: 3 April 2018 / Published: 4 April 2018
Cited by 1 | PDF Full-text (185 KB) | HTML Full-text | XML Full-text
Abstract
Only a handful of materials are well-established in three-dimensional (3D) printing and well-accepted in industrial manufacturing applications. However, recent advances in 3D printable materials have shown potential for enabling numerous novel applications in the future. This special issue, consisting of 2 reviews and
[...] Read more.
Only a handful of materials are well-established in three-dimensional (3D) printing and well-accepted in industrial manufacturing applications. However, recent advances in 3D printable materials have shown potential for enabling numerous novel applications in the future. This special issue, consisting of 2 reviews and 10 research articles, intends to explore the possible materials that could define next-generation 3D printing. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)

Research

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Open AccessArticle 3D Printability of Alginate-Carboxymethyl Cellulose Hydrogel
Materials 2018, 11(3), 454; https://doi.org/10.3390/ma11030454
Received: 3 February 2018 / Revised: 7 March 2018 / Accepted: 8 March 2018 / Published: 20 March 2018
Cited by 1 | PDF Full-text (20226 KB) | HTML Full-text | XML Full-text
Abstract
Three-dimensional (3D) bio-printing is a revolutionary technology to reproduce a 3D functional living tissue scaffold in-vitro through controlled layer-by-layer deposition of biomaterials along with high precision positioning of cells. Due to its bio-compatibility, natural hydrogels are commonly considered as the scaffold material. However,
[...] Read more.
Three-dimensional (3D) bio-printing is a revolutionary technology to reproduce a 3D functional living tissue scaffold in-vitro through controlled layer-by-layer deposition of biomaterials along with high precision positioning of cells. Due to its bio-compatibility, natural hydrogels are commonly considered as the scaffold material. However, the mechanical integrity of a hydrogel material, especially in 3D scaffold architecture, is an issue. In this research, a novel hybrid hydrogel, that is, sodium alginate with carboxymethyl cellulose (CMC) is developed and systematic quantitative characterization tests are conducted to validate its printability, shape fidelity and cell viability. The outcome of the rheological and mechanical test, filament collapse and fusion test demonstrate the favorable shape fidelity. Three-dimensional scaffold structures are fabricated with the pancreatic cancer cell, BxPC3 and the 86% cell viability is recorded after 23 days. This hybrid hydrogel can be a potential biomaterial in 3D bioprinting process and the outlined characterization techniques open an avenue directing reproducible printability and shape fidelity. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessArticle Design and 4D Printing of Cross-Folded Origami Structures: A Preliminary Investigation
Materials 2018, 11(3), 376; https://doi.org/10.3390/ma11030376
Received: 19 January 2018 / Revised: 26 February 2018 / Accepted: 28 February 2018 / Published: 3 March 2018
Cited by 2 | PDF Full-text (18046 KB) | HTML Full-text | XML Full-text
Abstract
In 4D printing research, different types of complex structure folding and unfolding have been investigated. However, research on cross-folding of origami structures (defined as a folding structure with at least two overlapping folds) has not been reported. This research focuses on the investigation
[...] Read more.
In 4D printing research, different types of complex structure folding and unfolding have been investigated. However, research on cross-folding of origami structures (defined as a folding structure with at least two overlapping folds) has not been reported. This research focuses on the investigation of cross-folding structures using multi-material components along different axes and different horizontal hinge thickness with single homogeneous material. Tensile tests were conducted to determine the impact of multi-material components and horizontal hinge thickness. In the case of multi-material structures, the hybrid material composition has a significant impact on the overall maximum strain and Young’s modulus properties. In the case of single material structures, the shape recovery speed is inversely proportional to the horizontal hinge thickness, while the flexural or bending strength is proportional to the horizontal hinge thickness. A hinge with a thickness of 0.5 mm could be folded three times prior to fracture whilst a hinge with a thickness of 0.3 mm could be folded only once prior to fracture. A hinge with a thickness of 0.1 mm could not even be folded without cracking. The introduction of a physical hole in the center of the folding/unfolding line provided stress relief and prevented fracture. A complex flower petal shape was used to successfully demonstrate the implementation of overlapping and non-overlapping folding lines using both single material segments and multi-material segments. Design guidelines for establishing cross-folding structures using multi-material components along different axes and different horizontal hinge thicknesses with single or homogeneous material were established. These guidelines can be used to design and implement complex origami structures with overlapping and non-overlapping folding lines. Combined overlapping folding structures could be implemented and allocating specific hole locations in the overall designs could be further explored. In addition, creating a more precise prediction by investigating sets of in between hinge thicknesses and comparing the folding times before fracture, will be the subject of future work. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessArticle A 3D-Printable Polymer-Metal Soft-Magnetic Functional Composite—Development and Characterization
Materials 2018, 11(2), 189; https://doi.org/10.3390/ma11020189
Received: 29 December 2017 / Revised: 18 January 2018 / Accepted: 22 January 2018 / Published: 25 January 2018
Cited by 2 | PDF Full-text (3371 KB) | HTML Full-text | XML Full-text
Abstract
In this work, a 3D printed polymer–metal soft-magnetic composite was developed and characterized for its material, structural, and functional properties. The material comprises acrylonitrile butadiene styrene (ABS) as the polymer matrix, with up to 40 vol. % stainless steel micropowder as the filler.
[...] Read more.
In this work, a 3D printed polymer–metal soft-magnetic composite was developed and characterized for its material, structural, and functional properties. The material comprises acrylonitrile butadiene styrene (ABS) as the polymer matrix, with up to 40 vol. % stainless steel micropowder as the filler. The composites were rheologically analyzed and 3D printed into tensile and flexural test specimens using a commercial desktop 3D printer. Mechanical characterization revealed a linearly decreasing trend of the ultimate tensile strength (UTS) and a sharp decrease in Young’s modulus with increasing filler content. Four-point bending analysis showed a decrease of up to 70% in the flexural strength of the composite and up to a two-factor increase in the secant modulus of elasticity. Magnetic hysteresis characterization revealed retentivities of up to 15.6 mT and coercive forces of up to 4.31 kA/m at an applied magnetic field of 485 kA/m. The composite shows promise as a material for the additive manufacturing of passive magnetic sensors and/or actuators. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessArticle Polymer-Ceramic Composite Scaffolds: The Effect of Hydroxyapatite and β-tri-Calcium Phosphate
Materials 2018, 11(1), 129; https://doi.org/10.3390/ma11010129
Received: 9 October 2017 / Revised: 8 January 2018 / Accepted: 11 January 2018 / Published: 14 January 2018
Cited by 3 | PDF Full-text (4414 KB) | HTML Full-text | XML Full-text
Abstract
The design of bioactive scaffolds with improved mechanical and biological properties is an important topic of research. This paper investigates the use of polymer-ceramic composite scaffolds for bone tissue engineering. Different ceramic materials (hydroxyapatite (HA) and β-tri-calcium phosphate (TCP)) were mixed with poly-ε-caprolactone
[...] Read more.
The design of bioactive scaffolds with improved mechanical and biological properties is an important topic of research. This paper investigates the use of polymer-ceramic composite scaffolds for bone tissue engineering. Different ceramic materials (hydroxyapatite (HA) and β-tri-calcium phosphate (TCP)) were mixed with poly-ε-caprolactone (PCL). Scaffolds with different material compositions were produced using an extrusion-based additive manufacturing system. The produced scaffolds were physically and chemically assessed, considering mechanical, wettability, scanning electron microscopy and thermal gravimetric tests. Cell viability, attachment and proliferation tests were performed using human adipose derived stem cells (hADSCs). Results show that scaffolds containing HA present better biological properties and TCP scaffolds present improved mechanical properties. It was also possible to observe that the addition of ceramic particles had no effect on the wettability of the scaffolds. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessArticle Effects of T2 Heat Treatment on Microstructure and Properties of the Selective Laser Melted Aluminum Alloy Samples
Materials 2018, 11(1), 66; https://doi.org/10.3390/ma11010066
Received: 27 November 2017 / Revised: 27 December 2017 / Accepted: 30 December 2017 / Published: 3 January 2018
Cited by 1 | PDF Full-text (4599 KB) | HTML Full-text | XML Full-text
Abstract
In this paper, aluminum alloy samples were fabricated by selective laser melting (SLM) and subsequently T2 heat treatment was undertaken. In order to obtain comprehensive results, various experiments on densification, hardness, tensile strength, bending strength and microstructure characterization were carried out. The results
[...] Read more.
In this paper, aluminum alloy samples were fabricated by selective laser melting (SLM) and subsequently T2 heat treatment was undertaken. In order to obtain comprehensive results, various experiments on densification, hardness, tensile strength, bending strength and microstructure characterization were carried out. The results show that densification of samples after T2 heat treatment does not vary very much from the SLMed ones, while the Brinell hardness and strength decreases to about 50%. Moreover, the plasticity and fracture deflection increases about 3 fold. The effects on the microstructure and the mechanical properties of the SLMed aluminum alloy samples and subsequent T2 heat treatment were studied. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessArticle Visible Light Photoinitiator for 3D-Printing of Tough Methacrylate Resins
Materials 2017, 10(12), 1445; https://doi.org/10.3390/ma10121445
Received: 28 November 2017 / Revised: 17 December 2017 / Accepted: 18 December 2017 / Published: 19 December 2017
Cited by 4 | PDF Full-text (3703 KB) | HTML Full-text | XML Full-text
Abstract
Lithography-based additive manufacturing was introduced in the 1980s, and is still the method of choice for printing accurate plastic parts with high surface quality. Recent progress in this field has made tough photopolymer resins and cheap LED light engines available. This study presents
[...] Read more.
Lithography-based additive manufacturing was introduced in the 1980s, and is still the method of choice for printing accurate plastic parts with high surface quality. Recent progress in this field has made tough photopolymer resins and cheap LED light engines available. This study presents the influence of photoinitiator selection and post-processing on the thermomechanical properties of various tough photopolymers. The influence of three photoinitiators (Ivocerin, BAPO, and TPO-L) on the double-bond conversion and mechanical properties was investigated by mid infrared spectroscopy, dynamic mechanical analysis and tensile tests. It was found that 1.18 wt % TPO-L would provide the best overall results in terms of double-bond conversion and mechanical properties. A correlation between double-bond conversion, yield strength, and glass transition temperature was found. Elongation at break remained high after post-curing at about 80–100%, and was not influenced by higher photoinitiator concentration. Finally, functional parts with 41 MPa tensile strength, 82% elongation at break, and 112 °C glass transition temperature were printed on a 405 nm DLP (digital light processing) printer. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessArticle Ceramic-Based 4D Components: Additive Manufacturing (AM) of Ceramic-Based Functionally Graded Materials (FGM) by Thermoplastic 3D Printing (T3DP)
Materials 2017, 10(12), 1368; https://doi.org/10.3390/ma10121368
Received: 10 October 2017 / Revised: 9 November 2017 / Accepted: 25 November 2017 / Published: 28 November 2017
Cited by 2 | PDF Full-text (70685 KB) | HTML Full-text | XML Full-text
Abstract
In our study, we investigated the additive manufacturing (AM) of ceramic-based functionally graded materials (FGM) by the direct AM technology thermoplastic 3D printing (T3DP). Zirconia components with varying microstructures were additively manufactured by using thermoplastic suspensions with different contents of pore-forming agents (PFA),
[...] Read more.
In our study, we investigated the additive manufacturing (AM) of ceramic-based functionally graded materials (FGM) by the direct AM technology thermoplastic 3D printing (T3DP). Zirconia components with varying microstructures were additively manufactured by using thermoplastic suspensions with different contents of pore-forming agents (PFA), which were co-sintered defect-free. Different materials were investigated concerning their suitability as PFA for the T3DP process. Diverse zirconia-based suspensions were prepared and used for the AM of single- and multi-material test components. All of the samples were sintered defect-free, and in the end, we could realize a brick wall-like component consisting of dense (<1% porosity) and porous (approx. 5% porosity) zirconia areas to combine different properties in one component. T3DP opens the door to the AM of further ceramic-based 4D components, such as multi-color, multi-material, or especially, multi-functional components. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessFeature PaperArticle Experimental Exploration of Metal Cable as Reinforcement in 3D Printed Concrete
Materials 2017, 10(11), 1314; https://doi.org/10.3390/ma10111314
Received: 11 October 2017 / Revised: 8 November 2017 / Accepted: 8 November 2017 / Published: 16 November 2017
Cited by 6 | PDF Full-text (6956 KB) | HTML Full-text | XML Full-text
Abstract
The Material Deposition Method (MDM) is enjoying increasing attention as an additive method to create concrete mortar structures characterised by a high degree of form-freedom, a lack of geometrical repetition, and automated construction. Several small-scale structures have been realised around the world, or
[...] Read more.
The Material Deposition Method (MDM) is enjoying increasing attention as an additive method to create concrete mortar structures characterised by a high degree of form-freedom, a lack of geometrical repetition, and automated construction. Several small-scale structures have been realised around the world, or are under preparation. However, the nature of this construction method is unsuitable for conventional reinforcement methods to achieve ductile failure behaviour. Sometimes, this is solved by combining printing with conventional casting and reinforcing techniques. This study, however, explores an alternative strategy, namely to directly entrain a metal cable in the concrete filament during printing to serve as reinforcement. A device is introduced to apply the reinforcement. Several options for online reinforcement media are compared for printability. Considerations specific to the manufacturing process are discussed. Subsequently, pull-out tests on cast and printed specimens provide an initial characterisation of bond behaviour. Bending tests furthermore show the potential of this reinforcement method. The bond stress of cables in printed concrete was comparable to values reported for smooth rebar but lower than that of the same cables in cast concrete. The scatter in experimental results was high. When sufficient bond length is available, ductile failure behaviour for tension parallel to the filament direction can be achieved, even though cable slip occurs. Further improvements to the process should pave the way to achieve better post-crack resistance, as the concept in itself is feasible. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessFeature PaperArticle Selective Laser Sintering of Porous Silica Enabled by Carbon Additive
Materials 2017, 10(11), 1313; https://doi.org/10.3390/ma10111313
Received: 30 September 2017 / Revised: 5 November 2017 / Accepted: 13 November 2017 / Published: 16 November 2017
Cited by 1 | PDF Full-text (9263 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this study is to investigate the possibility of a freeform fabrication of porous ceramic parts through selective laser sintering (SLS). SLS was proposed to manufacture ceramic green parts because this additive manufacturing technique can be used to fabricate three-dimensional objects
[...] Read more.
The aim of this study is to investigate the possibility of a freeform fabrication of porous ceramic parts through selective laser sintering (SLS). SLS was proposed to manufacture ceramic green parts because this additive manufacturing technique can be used to fabricate three-dimensional objects directly without a mold, and the technique has the capability of generating porous ceramics with controlled porosity. However, ceramic printing has not yet fully achieved its 3D fabrication capabilities without using polymer binder. Except for the limitations of high melting point, brittleness, and low thermal shock resistance from ceramic material properties, the key obstacle lies in the very poor absorptivity of oxide ceramics to fiber laser, which is widely installed in commercial SLS equipment. An alternative solution to overcome the poor laser absorptivity via improving material compositions is presented in this study. The positive effect of carbon additive on the absorptivity of silica powder to fiber laser is discussed. To investigate the capabilities of the SLS process, 3D porous silica structures were successfully prepared and characterized. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Review

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Open AccessReview A Review of Selective Laser Melted NiTi Shape Memory Alloy
Materials 2018, 11(4), 519; https://doi.org/10.3390/ma11040519
Received: 28 February 2018 / Revised: 24 March 2018 / Accepted: 26 March 2018 / Published: 29 March 2018
Cited by 1 | PDF Full-text (6805 KB) | HTML Full-text | XML Full-text
Abstract
NiTi shape memory alloys (SMAs) have the best combination of properties among the different SMAs. However, the limitations of conventional manufacturing processes and the poor manufacturability of NiTi have critically limited its full potential applicability. Thus, additive manufacturing, commonly known as 3D printing,
[...] Read more.
NiTi shape memory alloys (SMAs) have the best combination of properties among the different SMAs. However, the limitations of conventional manufacturing processes and the poor manufacturability of NiTi have critically limited its full potential applicability. Thus, additive manufacturing, commonly known as 3D printing, has the potential to be a solution in fabricating complex NiTi smart structures. Recently, a number of studies on Selective Laser Melting (SLM) of NiTi were conducted to explore the various aspects of SLM-produced NiTi. Compared to producing conventional metals through the SLM process, the fabrication of NiTi SMA is much more challenging. Not only do the produced parts require a high density that leads to good mechanical properties, strict composition control is needed as well for the SLM NiTi to possess suitable phase transformation characteristics. Additionally, obtaining a good shape memory effect from the SLM NiTi samples is another challenging task that requires further understanding. This paper presents the results of the effects of energy density and SLM process parameters on the properties of SLM NiTi. Its shape memory properties and potential applications were then reviewed and discussed. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Open AccessFeature PaperReview Advanced Material Strategies for Next-Generation Additive Manufacturing
Materials 2018, 11(1), 166; https://doi.org/10.3390/ma11010166
Received: 29 December 2017 / Revised: 15 January 2018 / Accepted: 17 January 2018 / Published: 22 January 2018
Cited by 2 | PDF Full-text (3625 KB) | HTML Full-text | XML Full-text
Abstract
Additive manufacturing (AM) has drawn tremendous attention in various fields. In recent years, great efforts have been made to develop novel additive manufacturing processes such as micro-/nano-scale 3D printing, bioprinting, and 4D printing for the fabrication of complex 3D structures with high resolution,
[...] Read more.
Additive manufacturing (AM) has drawn tremendous attention in various fields. In recent years, great efforts have been made to develop novel additive manufacturing processes such as micro-/nano-scale 3D printing, bioprinting, and 4D printing for the fabrication of complex 3D structures with high resolution, living components, and multimaterials. The development of advanced functional materials is important for the implementation of these novel additive manufacturing processes. Here, a state-of-the-art review on advanced material strategies for novel additive manufacturing processes is provided, mainly including conductive materials, biomaterials, and smart materials. The advantages, limitations, and future perspectives of these materials for additive manufacturing are discussed. It is believed that the innovations of material strategies in parallel with the evolution of additive manufacturing processes will provide numerous possibilities for the fabrication of complex smart constructs with multiple functions, which will significantly widen the application fields of next-generation additive manufacturing. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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Other

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Open AccessFeature PaperViewpoint Grain Structure Control of Additively Manufactured Metallic Materials
Materials 2017, 10(11), 1260; https://doi.org/10.3390/ma10111260
Received: 1 October 2017 / Revised: 24 October 2017 / Accepted: 24 October 2017 / Published: 2 November 2017
Cited by 5 | PDF Full-text (7406 KB) | HTML Full-text | XML Full-text
Abstract
Grain structure control is challenging for metal additive manufacturing (AM). Grain structure optimization requires the control of grain morphology with grain size refinement, which can improve the mechanical properties of additive manufactured components. This work summarizes methods to promote fine equiaxed grains in
[...] Read more.
Grain structure control is challenging for metal additive manufacturing (AM). Grain structure optimization requires the control of grain morphology with grain size refinement, which can improve the mechanical properties of additive manufactured components. This work summarizes methods to promote fine equiaxed grains in both the additive manufacturing process and subsequent heat treatment. Influences of temperature gradient, solidification velocity and alloy composition on grain morphology are discussed. Equiaxed solidification is greatly promoted by introducing a high density of heterogeneous nucleation sites via powder rate control in the direct energy deposition (DED) technique or powder surface treatment for powder-bed techniques. Grain growth/coarsening during post-processing heat treatment can be restricted by presence of nano-scale oxide particles formed in-situ during AM. Grain refinement of martensitic steels can also be achieved by cyclic austenitizing in post-processing heat treatment. Evidently, new alloy powder design is another sustainable method enhancing the capability of AM for high-performance components with desirable microstructures. Full article
(This article belongs to the Special Issue NextGen Materials for 3D Printing)
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