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Open Access
Article
Publication date: 15 March 2022

Mehrshad Mehrpouya, Daniel Tuma, Tom Vaneker, Mohamadreza Afrasiabi, Markus Bambach and Ian Gibson

This study aims to provide a comprehensive overview of the current state of the art in powder bed fusion (PBF) techniques for additive manufacturing of multiple materials…

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Abstract

Purpose

This study aims to provide a comprehensive overview of the current state of the art in powder bed fusion (PBF) techniques for additive manufacturing of multiple materials. It reviews the emerging technologies in PBF multimaterial printing and summarizes the latest simulation approaches for modeling them. The topic of “multimaterial PBF techniques” is still very new, undeveloped, and of interest to academia and industry on many levels.

Design/methodology/approach

This is a review paper. The study approach was to carefully search for and investigate notable works and peer-reviewed publications concerning multimaterial three-dimensional printing using PBF techniques. The current methodologies, as well as their advantages and disadvantages, are cross-compared through a systematic review.

Findings

The results show that the development of multimaterial PBF techniques is still in its infancy as many fundamental “research” questions have yet to be addressed before production. Experimentation has many limitations and is costly; therefore, modeling and simulation can be very helpful and is, of course, possible; however, it is heavily dependent on the material data and computational power, so it needs further development in future studies.

Originality/value

This work investigates the multimaterial PBF techniques and discusses the novel printing methods with practical examples. Our literature survey revealed that the number of accounts on the predictive modeling of stresses and optimizing laser scan strategies in multimaterial PBF is low with a (very) limited range of applications. To facilitate future developments in this direction, the key information of the simulation efforts and the state-of-the-art computational models of multimaterial PBF are provided.

Details

Rapid Prototyping Journal, vol. 28 no. 11
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 18 August 2022

Cole Brauer and Daniel Aukes

Multimaterial components possess material boundaries that introduce potential points of failure. Graded material transitions can help mitigate the impact of these abrupt…

Abstract

Purpose

Multimaterial components possess material boundaries that introduce potential points of failure. Graded material transitions can help mitigate the impact of these abrupt property changes. This approach is becoming increasingly accessible through three-dimensional (3D) printing, but it has yet to be extensively studied for rapid prototyping processes that are limited in resolution or number of material types. This study aims to investigate methods for applying graded transitions when using manufacturing processes with these limitations.

Design/methodology/approach

This study introduces a series of transition types that have graded properties and are produced using a finite number of discrete materials. This study presents a workflow for generating, fabricating and testing these transition types. This study uses this workflow with two different manufacturing processes to characterize the impact of each transition type on the ultimate tensile strength of a component.

Findings

Graded transitions can improve the performance of a component if the proper transition type is used. For high-fidelity processes, the best performing transitions are those closest to a true gradient. For low-fidelity processes, the best performing transitions are those which provide a balance of graded properties and mechanical connection.

Research limitations/implications

The presented performance trends are specific to the studied processes and materials. Future work using different fabrication parameters can use the presented workflow to assess process-specific trends.

Originality/value

This work comprehensively compares different methods of creating graded transitions using discrete materials, including several novel approaches. It also provides a new design workflow that allows the design of graded transitions to be easily integrated into a 3D printing workflow.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 February 1998

Y. Chastel, C. Magny and F. Bay

A finite element model for multimaterial configurations is presented. The material behavior of each body within a composite material is given by an elastic‐viscoplastic…

Abstract

A finite element model for multimaterial configurations is presented. The material behavior of each body within a composite material is given by an elastic‐viscoplastic constitutive law. Automatic remeshing techniques which preserve the topology of the different bodies of material are used to simulate large deformations of the multiphasic system. An experimental set‐up has been designed in order to simulate the compaction of multilayer composite materials. Plasticine was chosen as a model material. Experimental results are used to validate the finite element model for consolidation of multilayer composites.

Details

Engineering Computations, vol. 15 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 30 August 2022

Dorcas Kaweesa, Lourdes Bobbio, Allison M. Beese and Nicholas Alexander Meisel

This study aims to investigate the tensile strength and elastic modulus of custom-designed polymer composites developed using voxel-based design. This study also evaluates…

Abstract

Purpose

This study aims to investigate the tensile strength and elastic modulus of custom-designed polymer composites developed using voxel-based design. This study also evaluates theoretical models, such as the rule of mixtures, Halpin–Tsai model, Cox–Krenchel model and the Young–Beaumont model and the ability to predict the mechanical properties of particle-reinforced composites based on changes in the design of rigid particles at the microscale within a flexible polymer matrix.

Design/methodology/approach

This study leverages the PolyJet process for voxel-printing capabilities and a design of experiments approach to define the microstructural design elements (i.e. aspect ratio, orientation, size and volume fraction) used to create custom-designed composites.

Findings

The comparison between the predictions and experimental results helps identify appropriate methods for determining the mechanical properties of custom-designed composites ensuring informed design decisions for improved mechanical properties.

Originality/value

This work centers on multimaterial additive manufacturing leveraging design freedom and material complexity to create a wide range of composite materials. This study highlights the importance of identifying the process, structure and property relationships in material design.

Article
Publication date: 1 March 2002

Mauricio E. Pilleux, Ahmad Safari, Mehdi Allahverdi, Youren Chen, Yicheng Lu and Mohsen A. Jafari

Three‐dimensional photonic bandgap (PBG) structures using alumina (Al2O3) as the high permittivity material were modeled and then the structures were fabricated by Fused…

Abstract

Three‐dimensional photonic bandgap (PBG) structures using alumina (Al2O3) as the high permittivity material were modeled and then the structures were fabricated by Fused Deposition of Multi‐materials (FDMM) technology. A finite element method and a real‐time electromagnetic wave propagation software were used to simulate and design the layered PBG structures for applications in the microwave frequency range. The modeling predicted a 3‐D photonic bandgap in the 16.5–23.5 GHz range. FDMM provides a computer‐controlled process to generate 3‐D structures, allowing high fabrication flexibility and efficiency. Electromagnetic measurements displayed the presence of a bandgap between 17.1–23.3 GHz, showing a good agreement with the predicted values. These PBG structures are potential candidates for applications in advanced communication systems.

Details

Rapid Prototyping Journal, vol. 8 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 20 April 2015

Abby Megan Paterson, Richard Bibb, R. Ian Campbell and Guy Bingham

– The purpose of this paper is to compare four different additive manufacturing (AM) processes to assess their suitability in the context of upper extremity splinting.

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Abstract

Purpose

The purpose of this paper is to compare four different additive manufacturing (AM) processes to assess their suitability in the context of upper extremity splinting.

Design/methodology/approach

This paper describes the design characteristics and subsequent fabrication of six different wrist splints using four different AM processes: laser sintering (LS), fused deposition modelling (FDM), stereolithography (SLA) and polyjet material jetting via Objet Connex. The suitability of each process was then compared against competing designs and processes from traditional splinting. The splints were created using a digital design workflow that combined recognised clinical best practice with design for AM principles.

Findings

Research concluded that, based on currently available technology, FDM was considered the least suitable AM process for upper extremity splinting. LS, SLA and material jetting show promise for future applications, but further research and development into AM processes, materials and splint design optimisation is required if the full potential is to be realised.

Originality/value

Unlike previous work that has applied AM processes to replicate traditional splint designs, the splints described are based on a digital design for AM workflow, incorporating novel features and physical properties not previously possible in clinical splinting. The benefits of AM for customised splint fabrication have been summarised. A range of AM processes have also been evaluated for splinting, exposing the limitations of existing technology, demonstrating novel and advantageous design features and opportunities for future research.

Details

Rapid Prototyping Journal, vol. 21 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 27 September 2022

Taylor Davis, Tracy W. Nelson and Nathan B. Crane

dding dopants to a powder bed could be a cost-effective method for spatially varying the material properties in laser powder bed fusion (LPBF) or for evaluating new…

Abstract

Purpose

dding dopants to a powder bed could be a cost-effective method for spatially varying the material properties in laser powder bed fusion (LPBF) or for evaluating new materials and processing relationships. However, these additions may impact the selection of processing parameters. Furthermore, these impacts may be different when depositing nanoparticles into the powder bed than when the same composition is incorporated into the powder particles as by ball milling of powders or mixing similarly sized powders. This study aims to measure the changes in the single bead characteristics with laser power, laser scan speed, laser spot size and quantity of zirconia nanoparticle dopant added to SS 316 L powder.

Design/methodology/approach

A zirconia slurry was inkjet-printed into a single layer of 316 SS powder and dried. Single bead experiments were conducted on the composite powder. The line type (continuous vs balling) and the melt pool geometry were compared at various levels of zirconia doping.

Findings

The balling regime expands dramatically with the zirconia dopant to both higher and lower energy density values indicating the presence of multiple physical mechanisms that influence the resulting melt track morphology. However, the energy density required for continuous tracks was not impacted as significantly by zirconia addition. These results suggest that the addition of dopants may alter the process parameter ranges suitable for the fabrication of high-quality parts.

Originality/value

This work provides new insight into the potential impact of material doping on the ranges of energy density values that form continuous lines in single bead tests. It also illustrates a potential method for spatially varying material composition for process development or even part optimization in powder bed fusion without producing a mixed powder that cannot be recycled.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 16 May 2008

K.H. Low and Yuqi Wang

To present a method to model woven fibre reinforced metal matrix composite for multilayer circuit boards.

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Abstract

Purpose

To present a method to model woven fibre reinforced metal matrix composite for multilayer circuit boards.

Design/methodology/approach

This paper presents a hybrid modelling method to model multilayer multimaterial composites with the combination of metallic and woven composite plies. Firstly, 3D unit cells of woven composite are idealized as orthotropic plies, while metallic layers are taken as isotropic plies. Secondly, the idealized composite plies and metallic plies are modelled into a 2D multilayer finite element (FE). Lastly, scalar damage parameters are used for damage modelling.

Findings

Based on this method, static and dynamic analysis of multilayer composite can be performed at both micro and board levels. Meanwhile, the hybrid model illustrates a good agreement with the experimental results and good computational efficiency required for FE simulation. Conceptually, this study is aimed to provide an efficient damage modelling techniques for laminate composites and flexible modelling methodology for further development of new composite material systems.

Research limitations/implications

Damaging testing and simulation is not involved, although damaging modelling method is presented.

Originality/value

This model has high flexibility and efficiency: the micro structure and properties of reinforced fibres, polymer matrix and metallic plies can be changed conveniently in 3D mechanics unit‐cell model; the 2D structure of geometry model provides a high‐computational efficiency in the numerical simulation. The presented work also provides the damage modelling methods, multi‐linear damage law and scalar damage parameters, to simulate damage behaviour after impact.

Details

Circuit World, vol. 34 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 22 August 2022

Manikandan Nachimuthu and Rajesh P.K.

This paper aims to provide a review of four-dimensional (4D) printing of shape memory polymers using inkjet printing technology. 4D printing refers to the…

Abstract

Purpose

This paper aims to provide a review of four-dimensional (4D) printing of shape memory polymers using inkjet printing technology. 4D printing refers to the three-dimensional (3D) printing of smart materials capable of shape change or function modification with respect to time when activated by external stimuli. Inkjet printing has gained popularity because of the technical advantages such as non-contact deposition, multi-material printing, high resolution, high speed of printing and minimal post processing. This review will serve as a platform for understanding the inkjet 4D printing process and the shape memory capability of the polymer structures printed using inkjet printing.

Design/methodology/approach

The approach used in this review was to search for and review research works related to inkjet 4D printing of shape memory polymers. The search period was limited for the duration 2013 to 2021 as the 4D printing technology came into light later in 2013. With the review of inkjet 4D printing of shape memory polymers, the shape memory capability of the inkjet-printed structures were also studied.

Findings

With the available research documents, it was found that the inkjet 4D printing technology gained momentum from 2016, three years after the introduction of the 4D printing technology. The key findings of this review show that inkjet 4D printing of shape memory polymers were primarily performed using commercial inkjet printers and polymer inks linked to the printers. Even though the inkjet printing technology is matured enough to print multiple materials, development of shape memory polymer inks for inkjet printability remains complex. To realize the full potential of inkjet 4D printing, novel polymer inks specific for inkjet printing needs development.

Research limitations/implications

The major limitation to this review was the availability of research papers for review. Even though inkjet printing technology has grown to popularity in the graphics printing and publishing industry since its inception in the 19th century, the technology still needs to evolve in the printing of 3D structures due to the limitations in synthesizing inks that are inkjet printable. However, this research will serve as a platform for understating the current status of inkjet 4D printing and the limitations of the technology.

Originality/value

This review focuses only on the inkjet 4D printing of shape memory polymers among the generally summarized 4D printing review papers available. Currently, 4D printing of shape memory polymers is carried out using only the commercially available polymer printers. Also, researchers do not have the flexibility of modifying the polymer inks linked to the printers. This review can spur more research into the development of novel polymer inks specific for inkjet printing.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 16 July 2021

Rana El-Dabaa and Islam Salem

Conventional motion mechanisms in adaptive skins require rigid kinematic mechanical systems that require sensors and actuation devices, hence impeding the adoption of…

203

Abstract

Purpose

Conventional motion mechanisms in adaptive skins require rigid kinematic mechanical systems that require sensors and actuation devices, hence impeding the adoption of zero-energy buildings. This paper aims to exploit wooden responsive actuators as a passive approach for adaptive facades with dynamic shading configurations. Wooden passive actuators are introduced as a passive responsive mechanism with zero-energy consumption.

Design/methodology/approach

The study encodes the embedded hygroscopic parameters of wood through 4D printing of wooden composites as a responsive wooden actuator. Several physical experiments focus on controlling the printed hygroscopic parameters based on the effect of 3D printing grain patterns and infill height on the wooden angle of curvature when exposed to variation in humidity. The printed hygroscopic parameters are applied on two types of wooden actuators with difference in the saturation percentage of wood in the wooden filaments specifically 20% and 40% for more control on the angle of curvature and response behavior.

Findings

The study presents the ability to print wooden grain patterns that result in single and double curved surfaces. Also, printing actuators with variation in infill height control each part of wooden actuator to response separately in a controlled passive behavior. The results show a passive programmed self-actuated mechanism that can enhance responsive façade design with zero-energy consumption through utilizing both material science and additive manufacturing mechanisms.

Originality/value

The study presents a set of controlled printed hygroscopic parameters that stretch the limits in controlling the response of printed wood to humidity instead of the typical natural properties of wood.

1 – 10 of 94