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1 – 10 of 262
Article
Publication date: 21 February 2022

Kyudong Kim, Heena Noh, Kijung Park, Hyun Woo Jeon and Sunghoon Lim

This study aims to model power demand and energy consumption of fused filament fabrication (FFF) for carbon fiber-reinforced polyether-ether-ketone (CFR-PEEK) based on a…

Abstract

Purpose

This study aims to model power demand and energy consumption of fused filament fabrication (FFF) for carbon fiber-reinforced polyether-ether-ketone (CFR-PEEK) based on a material addition rate (MAR), which is affected by process parameter changes in an FFF machine. Moreover, a virtual additive manufacturing (AM) plant handling multiple FFF machines and part designs is simulated to compare the energy and production dynamics of operational strategies that treat part orders differently based on their inherent MAR.

Design/methodology/approach

A full-factorial design of experiments considering major FFF parameters (i.e., layer thickness and printing speed) is planned to fabricate CFR-PEEK samples for each process parameter combination. Then, the MAR of each process parameter combination is calculated to derive regression models for average power demand and total energy consumption. Furthermore, a discrete-event simulation model for a virtual AM system of aircraft parts is built to analyze changes in power demand and energy consumption along with order lead time and production volume under three operational strategies (i.e., higher MAR first-out, first-in-first-out, and lower MAR first-out).

Findings

The MAR of FFF for CFR-PEEK plays a key role in energy dynamics in which a decrease in energy consumption dominates over an increase in power demand as the MAR increases. Furthermore, preferentially processing parts with a higher MAR in the AM system is the most beneficial strategy in both energy consumption and productivity.

Originality/value

The findings from this study show that the energy performance of CFR-PEEK applications in FFF should be understood with the MAR of an AM system because the impact of AM complexity on energy performance can be operationally controlled by managing the MAR of part orders for the entire AM system.

Details

Rapid Prototyping Journal, vol. 28 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 20 June 2017

Muhammad Hussam Khaliq, Rui Gomes, Célio Fernandes, João Nóbrega, Olga Sousa Carneiro and Luis Lima Ferrás

This work aims to provide additional insights regarding the practicability of using conventional materials in the fused filament fabrication (FFF) process.

Abstract

Purpose

This work aims to provide additional insights regarding the practicability of using conventional materials in the fused filament fabrication (FFF) process.

Design/methodology/approach

Two different acrylonitryle butadiene styrene (ABS) grades are studied and compared, aiming to check to what extent the regular ABS developed for conventional polymer processing, with a different rheology than the one provided for the FFF process, can also be used in this process (FFF).

Findings

The rheological results show that a general-purpose ABS (ABS-GP) melt is much more viscous and elastic than ABS-FFF. It is clear that using ABS-GP as feedstock material in the FFF process results in poor coalescence and adhesion between the extruded filaments, which has a detrimental effect on the mechanical properties of the printed specimens. Despite its lower performance, ABS-GP can be a good choice if the objective is to produce an aesthetical prototype. If the objective is to produce a functional prototype or a final part, its mechanical performance requirements will dictate the choice.

Originality/value

This work provides insightful information regarding the use of high viscosity materials on the 3D printing process.

Details

Rapid Prototyping Journal, vol. 23 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 30 June 2022

Miguel Ángel Caminero, Ana Romero Gutiérrez, Jesús Miguel Chacón, Eustaquio García-Plaza and Pedro José Núñez

The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material…

Abstract

Purpose

The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material wastage. In this study, 316L stainless-steel metal filled filaments were used to print metal parts using the extrusion-based fused filament fabrication (FFF) approach. The purpose of this study is to assess the effects of common FFF printing parameters on the geometric and mechanical performance of FFF manufactured 316L stainless-steel components.

Design/methodology/approach

The microstructural characteristics of the metal filled filament, three-dimensional (3D) printed green parts and final sintered parts were analysed. In addition, the dimensional accuracy of the green parts was evaluated, as well as the hardness, tensile properties, relative density, part shrinkage and the porosity of the sintered samples. Moreover, surface quality in terms of surface roughness after sintering was assessed. Predictive models based on artificial neural networks (ANNs) were used for characterizing dimensional accuracy, shrinkage, surface roughness and density. Additionally, the response surface method based on ANNs was applied to represent the behaviour of these parameters and to identify the optimum 3D printing conditions.

Findings

The effects of the FFF process parameters such as build orientation and nozzle diameter were significant. The pore distribution was strongly linked to the build orientation and printing strategy. Furthermore, porosity decreased with increased nozzle diameter, which increased mechanical performance. In contrast, lower nozzle diameters achieved lower roughness values and average deviations. Thus, it should be noted that the modification of process parameters to achieve greater geometrical accuracy weakened mechanical performance.

Originality/value

Near-dense 316L austenitic stainless-steel components using FFF technology were successfully manufactured. This study provides print guidelines and further information regarding the impact of FFF process parameters on the mechanical, microstructural and geometric performance of 3D printed 316L components.

Details

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

Keywords

Article
Publication date: 31 May 2022

Efe C. Balta and Atakan Altınkaynak

This paper aims to develop experimentally validated numerical models to accurately characterize the cross-sectional geometry of the deposited beads in a fused filament…

Abstract

Purpose

This paper aims to develop experimentally validated numerical models to accurately characterize the cross-sectional geometry of the deposited beads in a fused filament fabrication (FFF) process under various process conditions.

Design/methodology/approach

The presented numerical model is investigated under various fidelity with varying computational complexity. To this end, comparisons between the Newtonian, non-newtonian, isothermal and non-isothermal computational models are presented for the extrusion of polylactic acid material in an FFF process. The computational model is validated through an experimental study on an off-the-shelf FFF printer. Microscope images of experimentally printed FFF bead cross-sections corresponding to various printing conditions are digitally processed for the validation. In the experimental study, common practical printing conditions for an FFF process are tested, and the results are compared to the numerical model.

Findings

Microscope image analyses of the cross-sectional geometries of deposited beads show that the numerical model provides a precise characterization of the cross-sectional geometry under varying process parameters in terms of the cross-section outline, bead height and width. The results show that the nozzle-to-table distance has a great effect on the bead shape when compared to the extrusion rate at a given nozzle-to-table distance. Comparison of the various computational models show that the non-Newtonian isothermal model provides the best tradeoff between computational complexity and model accuracy.

Originality/value

The authors provide detailed computational models, including the extruder nozzle geometry for cases ranging from Newtonian isothermal models to non-Newtonian non-isothermal models with experimental validation. The validation study is conducted for practical process parameters that are commonly used in FFF in practice and show that the computational models provide an accurate depiction of the true process outputs. As the developed models can accurately predict process outputs, they can be used in further applications for process planning and parameter tuning.

Article
Publication date: 23 August 2021

Budi Arifvianto, Yuris Bahadur Wirawan, Urip Agus Salim, Suyitno Suyitno and Muslim Mahardika

The purpose of this study is to investigate the influences of extruder temperatures and raster orientations on the mechanical properties of polylactic-acid (PLA) material…

Abstract

Purpose

The purpose of this study is to investigate the influences of extruder temperatures and raster orientations on the mechanical properties of polylactic-acid (PLA) material processed by using fused filament fabrication (FFF).

Design/methodology/approach

In this research, the PLA specimens were first printed with nozzle or extruder temperatures of 205°C, 215°C and 225°C and then evaluated in terms of their physical, chemical and mechanical properties. An appropriate extruder temperature was then selected based on this experiment and used for the printing of the other PLA specimens having various raster orientations. A series of tensile tests were carried out again to investigate the influence of raster orientations on the tensile strength, tensile strain and elastic modulus of those FFF-processed PLA materials. In the end, the one-way ANOVA was applied for the statistical analysis and the Mohr’s circle was established to aid in the analysis of the data obtained in this experiment.

Findings

The result of this study shows that the chemistry, porosity, degree of crystallinity and mechanical properties (tensile strength, strain and elastic modulus) of the PLA material printed with a raster angle of 0° were all insensitive to the increasing extruder temperature from 205°C to 225°C. Meanwhile, the mechanical properties of such printed PLA material were obviously influenced by its raster orientation. In this case, a PLA material with a raster orientation parallel to its loading axis, i.e. those with a raster angle of θ = 0°, was found as the strongest material. Meanwhile, the raster configuration-oriented perpendicular to its loading axis or θ = 90° yielded the weakest PLA material. The results of the tensile tests for the PLA material printed with bidirectional raster orientations, i.e. θ = 0°/90° and 45°/−45° demonstrated their strengths with values falling between those of the materials having unidirectional raster θ = 0° and 90°. Furthermore, the result of the analysis by using a well-known Mohr’s circle confirmed the experimental tensile strengths and the failure mechanisms of the PLA material that had been printed with various raster orientations.

Originality/value

This study presented consistent results on the chemistry, physical, degree of crystallinity and mechanical properties of the FFF-processed PLA in responding to the increasing extruder temperature from 205°C to 225°C applied during the printing process. Unlike the results of the previous studies, all these properties were also found to be insensitive to the increase of extruder temperature. Also, the result of this research demonstrates the usability of Mohr’s circle in the analysis of stresses working on an FFF-processed PLA material in responding to the changes in raster orientation printed in this material.

Details

Rapid Prototyping Journal, vol. 27 no. 10
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 16 August 2021

Mohammad Rashidul Hassan, Hyun Woo Jeon, Gayeon Kim and Kijung Park

This study aims to identify the effects of infill patterns and infill percentages on the energy consumption (EC) of fused filament fabrication (FFF). With increasing…

Abstract

Purpose

This study aims to identify the effects of infill patterns and infill percentages on the energy consumption (EC) of fused filament fabrication (FFF). With increasing attention on carbon-fiber-reinforced–poly-ether-ether-ketone (CFR-PEEK) for practical applications in FFF, infill pattern and infill percentage for FFF can be properly controlled to achieve better energy performance of CFR-PEEK outputs. However, the effects of infill parameters on EC for FFF using CFR-PEEK have not been clearly addressed yet.

Design/methodology/approach

Using a full factorial experimental design, six types of infill patterns (rectilinear, grid, triangular, wiggle, fast honeycomb and full honeycomb) and four different infill percentages (25%, 50%, 75% and 100%) were considered for a design of experiments with three replicates. Then, analysis of variance, Tukey test and regression analysis were performed to investigate both the effects of infill pattern and infill percentage on energy performance during FFF.

Findings

EC is characterized to be high for the wiggle and triangular patterns and low for the rectilinear pattern during both the printing stage and the entire process. The wiggle pattern results in the greatest increase in EC, whereas the rectilinear pattern leads to the least increase in EC. Although EC during the FFF process increases as the infill percentage increases, the average power demand during the printing stage decreases.

Originality/value

Both the main and interaction effects of infill pattern and infill percentage are investigated to estimate EC and power during the different process stages of FFF.

Details

Rapid Prototyping Journal, vol. 27 no. 10
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 8 February 2021

Erfan Rezvani Ghomi, Saeideh Kholghi Eshkalak, Sunpreet Singh, Amutha Chinnappan, Seeram Ramakrishna and Roger Narayan

The potential implications of the three-dimensional printing (3DP) technology are growing enormously in the various health-care sectors, including surgical planning…

Abstract

Purpose

The potential implications of the three-dimensional printing (3DP) technology are growing enormously in the various health-care sectors, including surgical planning, manufacturing of patient-specific implants and developing anatomical models. Although a wide range of thermoplastic polymers are available as 3DP feedstock, yet obtaining biocompatible and structurally integrated biomedical devices is still challenging owing to various technical issues.

Design/methodology/approach

Polyether ether ketone (PEEK) is an organic and biocompatible compound material that is recently being used to fabricate complex design geometries and patient-specific implants through 3DP. However, the thermal and rheological features of PEEK make it difficult to process through the 3DP technologies, for instance, fused filament fabrication. The present review paper presents a state-of-the-art literature review of the 3DP of PEEK for potential biomedical applications. In particular, a special emphasis has been given on the existing technical hurdles and possible technological and processing solutions for improving the printability of PEEK.

Findings

The reviewed literature highlighted that there exist numerous scientific and technical means which can be adopted for improving the quality features of the 3D-printed PEEK-based biomedical structures. The discussed technological innovations will help the 3DP system to enhance the layer adhesion strength, structural stability, as well as enable the printing of high-performance thermoplastics.

Originality/value

The content of the present manuscript will motivate young scholars and senior scientists to work in exploring high-performance thermoplastics for 3DP applications.

Details

Rapid Prototyping Journal, vol. 27 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 27 January 2021

Miguel Ángel Caminero, Ana Romero, Jesús Miguel Chacón, Pedro José Núñez, Eustaquio García-Plaza and Gloria Patricia Rodríguez

Fused filament fabrication (FFF) technique using metal filled filaments in combination with debinding and sintering steps can be a cost-effective alternative for…

Abstract

Purpose

Fused filament fabrication (FFF) technique using metal filled filaments in combination with debinding and sintering steps can be a cost-effective alternative for laser-based powder bed fusion processes. The mechanical behaviour of FFF-metal materials is highly dependent on the processing parameters, filament quality and adjusted post-processing steps. In addition, the microstructural material properties and geometric characteristics are inherent to the manufacturing process. The purpose of this study is to characterize the mechanical and geometric performance of three-dimensional (3-D) printed FFF 316 L metal components manufactured by a low-cost desktop 3-D printer. The debinding and sintering processes are carried out using the BASF catalytic debinding process in combination with the BASF 316LX Ultrafuse filament. Special attention is paid on the effects of build orientation and printing strategy of the FFF-based technology on the tensile and geometric performance of the 3-D printed 316 L metal specimens.

Design/methodology/approach

This study uses a toolset of experimental analysis techniques [metallography and scanning electron microcope (SEM)] to characterize the effect of microstructure and defects on the material properties under tensile testing. Shrinkage and the resulting porosity of the 3-D printed 316 L stainless steel sintered samples are also analysed. The deformation behaviour is investigated for three different build orientations. The tensile test curves are further correlated with the damage surface using SEM images and metallographic sections to present grain deformation during the loading progress. Mechanical properties are directly compared to other works in the field and similar additive manufacturing (AM) and Metal Injection Moulding (MIM) manufacturing alternatives from the literature.

Findings

It has been shown that the effect of build orientation was of particular significance on the mechanical and geometric performance of FFF-metal 3-D printed samples. In particular, Flat and On-edge samples showed an average increase in tensile performance of 21.7% for the tensile strength, 65.1% for the tensile stiffness and 118.3% for maximum elongation at fracture compared to the Upright samples. Furthermore, it has been able to manufacture near-dense 316 L austenitic stainless steel components using FFF. These properties are comparable to those obtained by other metal conventional processes such as MIM process.

Originality/value

316L austenitic stainless steel components using FFF technology with a porosity lower than 2% were successfully manufactured. The presented study provides more information regarding the dependence of the mechanical, microstructural and geometric properties of FFF 316 L components on the build orientation and printing strategy.

Article
Publication date: 7 June 2013

Edmund C. Penning‐Rowsell, Edward P. Evans, Jim W. Hall and Alistair G.L. Borthwick

The Foresight Future Flooding (FFF) project researched flood risk in the UK to the year 2100 for central government, using scenarios and a national risk assessment model

1043

Abstract

Purpose

The Foresight Future Flooding (FFF) project researched flood risk in the UK to the year 2100 for central government, using scenarios and a national risk assessment model backed by qualitative analysis from panels of some 45 senior scientists. The purpose of this paper is to assess the impact of the project, both nationally and internationally.

Design/methodology/approach

This paper assesses the impact of the FFF project, both nationally and internationally, using web searches, document analysis, and a questionnaire survey of key actors in the flood risk management policy field.

Findings

It was found that the penetration of the project into professionals' consciousness was high in relation to other comparable projects and publications, and its impact on policy – both immediately and continuing – was profound. The FFF initiative did not create policy change, however, but facilitated its legitimation, adding impetus to what was already there, as one element of a part‐catalytic and part‐incremental process of policy evolution.

Research limitations/implications

Special circumstances, internal and external to the project, mean that this cannot be a simple model for matching research to policymakers' needs in the future.

Practical implications

Important lessons may be learnt from this project about both the methods of forward‐looking foresight‐type research, and the way that its results are disseminated to its target audiences.

Originality/value

This is an innovative attempt to assess the impact of a new type of foresight project.

Details

Foresight, vol. 15 no. 3
Type: Research Article
ISSN: 1463-6689

Keywords

Article
Publication date: 15 August 2019

Isaac Ferreira, Margarida Machado, Fernando Alves and António Torres Marques

In industry, fused filament fabrication (FFF) offers flexibility and agility by promoting a reduction in costs and in the lead-time (i.e. time-to-market). Nevertheless, FFF

Abstract

Purpose

In industry, fused filament fabrication (FFF) offers flexibility and agility by promoting a reduction in costs and in the lead-time (i.e. time-to-market). Nevertheless, FFF parts exhibit some limitations such as lack of accuracy and/or lower mechanical performance. As a result, some alternatives have been developed to overcome some of these restrictions, namely, the formulation of high performance polymers, the creation of fibre-reinforced materials by FFF process and/or the design of new FFF-based technologies for printing composite materials. This work aims to analyze these technologies.

Design/methodology/approach

This work aims to study and understand the advances in the behaviour of 3D printed parts with enhanced performance by its reinforcement with several shapes and types of fibres from nanoparticles to continuous fibre roving. Thus, a comprehensive survey of significant research studies carried out regarding FFF of fibre-reinforced thermoplastics is provided, giving emphasis to the most relevant and innovative developments or adaptations undergone at hardware level and/or on the production process of the feedstock.

Findings

It is shown that the different types of reinforcement present different challenges for the printing process with different outcomes in the part performance.

Originality/value

This review is focused on joining the most important researches dedicated to the process of FFF-printed parts with different types reinforcing materials. By dividing the reinforcements in categories by shape/geometry and method of processing, it is possible to better quantify performance improvements.

Details

Rapid Prototyping Journal, vol. 25 no. 6
Type: Research Article
ISSN: 1355-2546

Keywords

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