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1 – 10 of 158
Article
Publication date: 12 December 2023

Austin R. Colon, David Owen Kazmer, Amy M. Peterson and Jonathan E. Seppala

A main cause of defects within material extrusion (MatEx) additive manufacturing is the nonisothermal condition in the hot end, which causes inconsistent extrusion and polymer…

Abstract

Purpose

A main cause of defects within material extrusion (MatEx) additive manufacturing is the nonisothermal condition in the hot end, which causes inconsistent extrusion and polymer welding. This paper aims to validate a custom hot end design intended to heat the thermoplastic to form a melt prior to the nozzle and to reduce variability in melt temperature. A full 3D temperature verification methodology for hot ends is also presented.

Design/methodology/approach

Infrared (IR) thermography of steady-state extrusion for varying volumetric flow rates, hot end temperature setpoints and nozzle orifice diameters provides data for model validation. A finite-element model is used to predict the temperature of the extrudate. Model tuning demonstrates the effects of different model assumptions on the simulated melt temperature.

Findings

The experimental results show that the measured temperature and variance are functions of volumetric flow rate, temperature setpoint and the nozzle orifice diameter. Convection to the surrounding air is a primary heat transfer mechanism. The custom hot end brings the melt to its setpoint temperature prior to entering the nozzle.

Originality/value

This work provides a full set of steady-state IR thermography data for various parameter settings. It also provides insight into the performance of a custom hot end designed to improve the robustness of melting in MatEx. Finally, it proposes a strategy for modeling such systems that incorporates the metal components and the air around the system.

Details

Rapid Prototyping Journal, vol. 30 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 19 October 2022

Sermet Demir and Caner Yüksel

The purpose of this paper is to analyze the effect of printing parameters on the mechanical properties of standard dog bone specimens manufactured by fused deposition modeling.

Abstract

Purpose

The purpose of this paper is to analyze the effect of printing parameters on the mechanical properties of standard dog bone specimens manufactured by fused deposition modeling.

Design/methodology/approach

Polylactic acid (PLA) specimens were printed and tested according to the ASTM standard. The effect of five important printing parameters, layer height, raster angle, printing speed, nozzle temperature and nozzle diameter, was examined on ultimate tensile strength (UTS), elongation and apparent density. Five levels were attended for each parameter, and a high number of required experiments were reduced by applying the L25 Taguchi design of the experiment.

Findings

The effect of each parameter on outputs and optimal values for maximum tensile strength were determined. The most influential parameter is the raster angle of 64.96%. Nozzle temperature has a low effect of 1.76%, but nozzle diameter contribution is 9.77%. The experiment results are validated by analysis of variance analysis, and the optimal predicted level for parameters is 90° raster angle, 0.2 mm layer height, 100 mm/s printing speed, 200°C nozzle temperature and 0.8 mm nozzle diameter. The maximum UTS observed is 48.70 MPa for 0.8 mm nozzle diameter, whereas the minimum is 18.49 for 0.2 mm nozzle diameter.

Originality/value

This paper is a very extensive experimental research report on the effect of the parameters for the tensile property of 3D printed PLA specimens by the Taguchi method. The documented results can be further developed for an optimization model to obtain a desired mechanical property with less variation and uncertainty in a product.

Details

Rapid Prototyping Journal, vol. 29 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 9 December 2022

Jiaru Shao, Xueping Mo, Zijun Zheng and Yu Yang

This study aims to improve the survivability and maneuverability of the fighter,and study the stealth performance of fighter in the jet noise of aeroengine, it is of great…

Abstract

Purpose

This study aims to improve the survivability and maneuverability of the fighter,and study the stealth performance of fighter in the jet noise of aeroengine, it is of great significance to study the jet noise characteristics of double S-bend nozzles.

Design/methodology/approach

The multiparameter coupling and super-ellipse design methods are used to design the cross section of double S-bend nozzle. Taking unsteady flow information as the equivalent sound source, the noise signal at the far-field monitoring points were calculated with Ffowcs Williams–Hawkings (FW–H) method, and then, the sound source characteristics of the double S-bend nozzle are analyzed.

Findings

The results show that the internal flow of the S-bend nozzle with rectangular section is smoothed and the aerodynamic performance is better than super-ellipse section, the shear layer length of rectangular section is longer, the thickness is smaller and the mixing ability is stronger. The sound pressure level of the two S-bend nozzles decreases with the increase of the monitoring angle, and the sound pressure on the horizontal plane is greater than the vertical plane. In the direction of 40°–120°, the jet noise of rectangular nozzle is smaller, and the multiparameter coupled rectangular cross section structure is more applicable.

Practical implications

It is beneficial to reduce the jet noise of the engine tail nozzle and improve the stealth performance of the aircraft.

Originality/value

There is very little research on the jet noise characteristics of the double S-bend nozzle. The multiparameter coupling and the super-ellipse method are used to design the nozzle flow section to study the aerodynamic performance and jet noise characteristics of the double S-bend nozzle and to improve the acoustic stealth characteristics of the aircraft.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 2 February 2024

Ferhat Ceritbinmez and Ali Günen

This study aims to comparatively analyze the cut parts obtained as a result of cutting the Ni-based Inconel 625 alloy, which is widely used in the aerospace industry, with the…

Abstract

Purpose

This study aims to comparatively analyze the cut parts obtained as a result of cutting the Ni-based Inconel 625 alloy, which is widely used in the aerospace industry, with the wire electro-discharge machining (WEDM) and abrasive water jet machining (AWJM) methods in terms of macro- and microanalyses.

Design/methodology/approach

In this study, calipers, Mitutoyo SJ-210, Nikon SMZ 745 T, scanning electron microscope and energy dispersive X-ray were used to determine kerf, surface roughness and macro- and microanalyses.

Findings

Considering the applications in the turbine industry, it has been determined that the WEDM method is suitable to meet the standards for the machinability of Inconel 625 alloy. In contrast, the AWJM method does not meet the standards. Namely, while the kerf angle was formed because the hole entrance diameters of the holes obtained with AWJM were larger than the hole exit diameters, the equalization of the hole entry and exit dimensions, thanks to the perpendicularity and tension sensitivity of the wire electrode used in the holes drilled with WEDM ensured that the kerf angle was not formed.

Originality/value

It is known that the surface roughness of the parts used in the turbine industry is accepted at Ra = 0.8 µm. In this study, the average roughness value obtained from the successful drilling of Inconel 625 alloy with the WEDM method was 0.799 µm, and the kerf angle was obtained as zero. In the cuts made with the AWJM method, thermal effects such as debris, microcracks and melted materials were not observed; an average surface roughness of 2.293 µm and a kerf of 0.976° were obtained.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 3 January 2023

Mohammad Saleh Afsharkohan, Saman Dehrooyeh, Majid Sohrabian and Majid Vaseghi

Fabrication settings such as printing speed and nozzle temperature in fused deposition modeling undeniably influence the quality and strength of fabricated parts. As available…

Abstract

Purpose

Fabrication settings such as printing speed and nozzle temperature in fused deposition modeling undeniably influence the quality and strength of fabricated parts. As available market filaments do not contain any exact information report for printing settings, manufacturers are incapable of achieving desirable predefined print accuracy and mechanical properties for the final parts. The purpose of this study is to determine the importance of selecting suitable print parameters by understanding the intrinsic behavior of the material to achieve high-performance parts.

Design/methodology/approach

Two common commercial polylactic acid filaments were selected as the investigated samples. To study the specimens’ printing quality, an appropriate scaffold geometry as a delicate printing sample was printed according to a variety of speeds and nozzle temperatures, selected in the filament manufacturer’s proposed temperature range. Dimensional accuracy and qualitative surface roughness of the specimens made by one of the filaments were evaluated and the best processing parameters were selected. The scaffolds were fabricated again by both filaments according to the selected proper processing parameters. Material characterization tests were accomplished to study the reason for different filament behaviors in the printing process. Moreover, the correlations between the polymer structure, thermo-rheological behavior and printing parameters were denoted.

Findings

Compression tests revealed that precise printing of the characterized filament results in more accurate structure and subsequent improvement of the final printed sample elastic modulus.

Originality/value

The importance of material characterization to achieve desired properties for any purpose was emphasized. Obtained results from the rheological characterizations would help other users to benefit from the highest performance of their specific filament.

Details

Rapid Prototyping Journal, vol. 29 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 26 January 2024

Silvia Badini, Serena Graziosi, Michele Carboni, Stefano Regondi and Raffaele Pugliese

This study evaluates the potential of using the material extrusion (MEX) process for recycling waste tire rubber (WTR). By investigating the process parameters, mechanical…

Abstract

Purpose

This study evaluates the potential of using the material extrusion (MEX) process for recycling waste tire rubber (WTR). By investigating the process parameters, mechanical behaviour and morphological characterisation of a thermoplastic polyurethane-waste tire rubber composite filament (TPU-WTR), this study aims to establish a framework for end-of-life tire (ELT) recycling using the MEX technology.

Design/methodology/approach

The research assesses the impact of various process parameters on the mechanical properties of the TPU-WTR filament. Hysteresis analysis and Poisson’s ratio estimation are conducted to investigate the material’s behaviour. In addition, the compressive performance of diverse TPU-WTR triply periodic minimal surface lattices is explored to test the filament suitability for printing intricate structures.

Findings

Results demonstrate the potential of the TPU-WTR filament in developing sustainable structures. The MEX process can, therefore, contribute to the recycling of WTR. Mechanical testing has provided insights into the influence of process parameters on the material behaviour, while investigating various lattice structures has challenged the material’s capabilities in printing complex topologies.

Social implications

This research holds significant social implications addressing the growing environmental sustainability and waste management concerns. Developing 3D-printed sustainable structures using recycled materials reduces resource consumption and promotes responsible production practices for a more environmentally conscious society.

Originality/value

This study contributes to the field by showcasing the use of MEX technology for ELT recycling, particularly focusing on the TPU-WTR filament, presenting a novel approach to sustainable consumption and production aligned with the United Nations Sustainable Development Goal 12.

Article
Publication date: 20 December 2023

Prashant Anerao, Atul Kulkarni and Yashwant Munde

This paper aims to investigate the current state of biocomposites used in fused deposition modelling (FDM) with a focus on their mechanical characteristics.

Abstract

Purpose

This paper aims to investigate the current state of biocomposites used in fused deposition modelling (FDM) with a focus on their mechanical characteristics.

Design/methodology/approach

The study presents a variety of biocomposite materials that have been used in filaments for 3D printing by different researchers. The process of making filaments is then described, followed by a discussion of the process parameters associated with the FDM.

Findings

To achieve better mechanical properties of 3D-printed parts, it is essential to optimize the process parameters of FDM while considering the characteristics of the biocomposite material. Polylactic acid is considered the most promising matrix material due to its biodegradability and lower cost. Moreover, the use of natural fibres like hemp, flax and sugarcane bagasse as reinforcement to the polymer in FDM filaments improves the mechanical performance of printed parts.

Originality/value

The paper discusses the influence of critical process parameters of FDM like raster angle, layer thickness, infill density, infill pattern and extruder temperature on the mechanical properties of 3D-printed biocomposite.

Details

Rapid Prototyping Journal, vol. 30 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 28 August 2023

Shekhar Sharma, Saurav Datta, Tarapada Roy and Siba Sankar Mahapatra

Fused filament fabrication (FFF) is a type of additive manufacturing (AM) based on materials extrusion. It is the most widely practiced AM route, especially used for polymer-based…

Abstract

Purpose

Fused filament fabrication (FFF) is a type of additive manufacturing (AM) based on materials extrusion. It is the most widely practiced AM route, especially used for polymer-based rapid prototyping and customized product fabrication in relation to aerospace, automotive, architecture, consumer goods and medical applications. During FFF, part quality (surface finish, dimensional accuracy and static mechanical strength) is greatly influenced by several process parameters. The paper aims to study FFF parametric influence on aforesaid part quality aspects. In addition, dynamic analysis of the FFF part is carried out.

Design/methodology/approach

Interpretive structural modelling is attempted to articulate interrelationships that exist amongst FFF parameters. Next, a few specimens are fabricated using acrylonitrile butadiene styrene plastic at varied build orientation and build style. Effects of build orientation and build style on part’s ultimate tensile strength, flexure strength along with width build time are studied. Prototype beams (of different thickness) are fabricated by varying build style. Instrumental impact hammer Modal analysis is performed on the cantilever beams (cantilever support) to obtain the natural frequencies (first mode). Parametric influence on natural frequencies is also studied.

Findings

Static mechanical properties (tensile and flexure strength) are greatly influenced by build style and build orientation. Natural frequency (NF) of prototype beams is highly influenced by the build style and beam thickness.

Originality/value

FFF built parts when subjected to application, may have to face a variety of external dynamic loads. If frequency of induced vibration (due to external force) matches with NF of the component part, resonance is incurred. To avoid occurrence of resonance, operational frequency (frequency of externally applied forces) must be lower/ higher than the NF. Because NF depends on mass and stiffness, and boundary conditions, FFF parts produced through varying build style may definitely correspond to varied NF. This aspect is explained in this work.

Details

Rapid Prototyping Journal, vol. 29 no. 10
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 20 March 2024

Hakan F. Oztop, Burak Kiyak and Ishak Gökhan Aksoy

This study aims to focus on understanding how different jet angles and Reynolds numbers influence the phase change materials’ (PCMs) melting process and their capacity to store…

Abstract

Purpose

This study aims to focus on understanding how different jet angles and Reynolds numbers influence the phase change materials’ (PCMs) melting process and their capacity to store energy. This approach is intended to offer novel insights into enhancing thermal energy storage systems, particularly for applications where heat transfer efficiency and energy storage are critical.

Design/methodology/approach

The research involved an experimental and numerical analysis of PCM with a melting temperature range of 22 °C–26°C under various conditions. Three different jet angles (45°, 90° and 135°) and two container angles (45° and 90°) were tested. Additionally, two different Reynolds numbers (2,235 and 4,470) were used to explore the effects of jet outlet velocities on PCM melting behaviour. The study used a circular container and analysed the melting process using the hot air inclined jet impingement (HAIJI) method.

Findings

The obtained results showed that the average temperature for the last time step at Ф = 90° and Re = 4,470 is 6.26% higher for Ф = 135° and 14.23% higher for Ф = 90° compared with the 45° jet angle. It is also observed that the jet angle, especially for Ф = 90°, is a much more important factor in energy storage than the Reynolds number. In other words, the jet angle can be used as a passive control parameter for energy storage.

Originality/value

This study offers a novel perspective on the effective storage of waste heat transferred with air, such as exhaust gases. It provides valuable insights into the role of jet inclination angles and Reynolds numbers in optimizing the melting and energy storage performance of PCMs, which can be crucial for enhancing the efficiency of thermal energy storage systems.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 20 October 2022

Donghua Zhao, Jiapeng He, Gaohan Zhu, Youcheng Han and Weizhong Guo

The rapid development of three-dimensional (3D) printing makes it familiar in daily life, especially the fused deposition modeling 3D printers. The process planning of traditional…

Abstract

Purpose

The rapid development of three-dimensional (3D) printing makes it familiar in daily life, especially the fused deposition modeling 3D printers. The process planning of traditional flat layer printing includes slicing and path planning to obtain the boundaries and the filling paths for each layer along the vertical direction. There is a clear division line through the whole fabricated part, inherited in the flat-layer-based printed parts. This problem is brought about by the seam of the boundary in each layer. Hence, the purpose of this paper is to propose a novel helical filling path generation with the ideal surface-plane intersection for a rotary 3D printer.

Design/methodology/approach

The detailed algorithm and implementation steps are given with several worked examples to enable readers to understand it better. The adjacent points obtained from the planar slicing are combined to generate each layer's helical points. The contours of all layers are traversed to obtain the helical surface layer and helical path. Meanwhile, the novel rotary four-degree of freedom 3D printer is briefly introduced.

Findings

As a proof of concept, this paper presents several examples based on the rotary 3D printer designed in the authors’ previous research and the algorithms illustrated in this paper. The preliminary experiments successfully verify the feasibility and versatility of the proposed slicing method based on a rotary 3D printer.

Originality/value

This paper provides a novel and feasible slicing method for multi-axis rotary 3D printers, making manufacturing thin-wall and complex parts possible. To further broaden the proposed slicing method’s application in further research, adaptive tool path generation for flat and curved layer printing could be applied with a combination of flat and curved layers in the same layer, different layers or even different parts of structures.

1 – 10 of 158