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Article
Publication date: 9 April 2018

Harlal S. Mali, Bhargav Prajwal, Divyanshu Gupta and Jai Kishan

The purpose of this paper is to study the integration between fused deposition modeling (FDM) technology and abrasive flow machining process to improve the surface quality…

Abstract

Purpose

The purpose of this paper is to study the integration between fused deposition modeling (FDM) technology and abrasive flow machining process to improve the surface quality of FDM printed parts. FDM process has some limitations in terms of accuracy and surface finish. Hence, post-processing operations are essential to increase the quality of the part.

Design/methodology/approach

Initially, a sustainable polymer abrasive gel-based media (SPAGM) using natural polymer and natural additives (waste vegetable oil) was prepared using different combinations of (abrasive mesh size, percentage of abrasives and percentage of liquid synthesizer); then the characterization of media was done to check various properties. As media is an essential part in the process which helps in increase the surface finish, it needs to have some desired characteristics such as the following: the developed SPAG needs to hold the abrasives; its viscosity has to be medium so that it can easily flow through the machine; and its thermal stability caused by the increase in the temperature during various cycles of operation. For that, it is characterized rheologically as well as thermally to find its various properties.

Findings

Experiments were performed on FDM-printed parts using an L9 orthogonal array with different parameters to find their effect on the workpiece. Scanning electron microscope images of SGAPM showed sharp edges of abrasive particles and bonding pattern between polymer chain molecules. Good surface finish and material removal rate (MRR) was observed at high pressure and long finishing time with 50 per cent abrasive concentration.

Originality/value

The authors confirm that this work is original and has neither been published elsewhere nor is it currently under consideration for publication elsewhere.

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Article
Publication date: 31 August 2021

Nitin Dixit, Varun Sharma and Pradeep Kumar

The surface roughness of additively manufactured parts is usually found to be high. This limits their use in industrial and biomedical applications. Therefore, these parts…

Abstract

Purpose

The surface roughness of additively manufactured parts is usually found to be high. This limits their use in industrial and biomedical applications. Therefore, these parts required post-processing to improve their surface quality. The purpose of this study is to finish three-dimensional (3D) printed acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) parts using abrasive flow machining (AFM).

Design/methodology/approach

A hydrogel-based abrasive media has been developed to finish 3D printed parts. The developed abrasive media has been characterized for its rheology and thermal stability using sweep tests, thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The ABS and PLA cylindrical parts have been prepared using fused deposition modeling (FDM) and finished using AFM. The experiments were designed using Taguchi (L9 OA) method. The effect of process parameters such as extrusion pressure (EP), layer thickness (LT) and abrasive concentration (AC) was investigated on the amount of material removed (MR) and percentage improvement in surface roughness (%ΔRa).

Findings

The developed abrasive media was found to be effective for finishing FDM printed parts using AFM. The microscope images of unfinished and finished showed a significant improvement in surface topography of additively manufactures parts after AFM. The results reveal that AC is the most significant parameter during the finishing of ABS parts. However, EP and AC are the most significant parameters for MR and %ΔRa, respectively, during the finishing of PLA parts.

Practical implications

The FDM technology has applications in the biomedical, electronics, aeronautics and defense sectors. PLA has good biodegradable and biocompatible properties, so widely used in biomedical applications. The ventilator splitters fabricated using FDM have a profile similar to the shape used in the present study.

Research limitations/implications

The present study is focused on finishing FDM printed cylindrical parts using AFM. Future research may be done on the AFM of complex shapes and freeform surfaces printed using different additive manufacturing (AM) techniques.

Originality/value

An abrasive media consists of xanthan gum, locust bean gum and fumed silica has been developed and characterized. An experimental study has been performed by combining printing parameters of FDM and finishing parameters of AFM. A comparative analysis in MR and %ΔRa has been reported between 3D printed ABS and PLA parts.

Details

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

Keywords

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Article
Publication date: 3 April 2007

Robert E. Williams, Daniel F. Walczyk and Hoang T. Dang

To determine the feasibility of sealing and finishing conformal cooling/heating channels in profiled edge laminae (PEL) rapid tooling (RT) using abrasive flow machining (AFM).

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Abstract

Purpose

To determine the feasibility of sealing and finishing conformal cooling/heating channels in profiled edge laminae (PEL) rapid tooling (RT) using abrasive flow machining (AFM).

Design/methodology/approach

Sample PEL tools constructed of both aluminum and steel were designed and assembled for finishing by AFM. A simple design of experiments approach was utilized. Output parameters of interest included the material removal, surface roughness improvement and, most importantly, the ability to withstand a pressurized oil leak test.

Findings

AFM significantly improved the finish in the channels for aluminum and steel PEL tooling. Leak testing found that AFM also improved the sealing of both stacks at static pressures up to 690 kPa. The steel tooling appeared to benefit more from the AFM process. It has been postulated that the primary cause of the sealing is the plastic deformation of workpiece material in the plowing mode.

Research limitations/implications

The conformal channels studied had a simple cross‐sectional geometry and straight runs. The PEL tools were only made of two materials. However, the research results show great promise for large RT, including thermoforming and composite forming molds where temperature control is a critical issue.

Practical implications

The ability to seal the interfaces between individual laminae expands the potential application of AFM tremendously. AFM also has the potential to finish a wide range of internal passages in a variety of RT.

Originality/value

AFM has been previously used for finishing stereolithography prototypes. This is the first known attempt to seal and finish channels in laminated RT using AFM.

Details

Rapid Prototyping Journal, vol. 13 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 1 June 1998

Robert E. Williams and Vicki L. Melton

This research investigated the use of two relatively new technologies, abrasive flow machining (AFM) and stereolithography (SL), to minimize the time to develop a finished…

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1413

Abstract

This research investigated the use of two relatively new technologies, abrasive flow machining (AFM) and stereolithography (SL), to minimize the time to develop a finished prototype. Statistical analysis was used to determine effects of media grit size, media pressure, build style, build orientation and resin type on flatness, material removal rate and surface roughness. Results indicated that media pressure, grit size, and build orientation were significant in at least one of the experiments performed. Scanning electron microscope (SEM) images showed the stair‐stepping effect of the SL process before AFM and the removal of the stair‐stepping after AFM. The SEM images showed a lack of typical AFM flowlines on the surface and suggested that the workpiece material is removed by brittle fracture. Data dependent systems analysis techniques were also used to study the surface roughness profiles.

Details

Rapid Prototyping Journal, vol. 4 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 9 July 2020

Julian Ferchow, Harry Baumgartner, Christoph Klahn and Mirko Meboldt

Internal channels produced by selective laser melting (SLM) have rough surfaces that require post-processing. The purpose of this paper is to develop an empirical model…

Abstract

Purpose

Internal channels produced by selective laser melting (SLM) have rough surfaces that require post-processing. The purpose of this paper is to develop an empirical model for predicting the material removal and surface roughness (SR) of SLM-manufactured channels owing to abrasive flow machining (AFM).

Design/methodology/approach

A rheological model was developed to simulate the viscosity and power-law index of an AFM medium. To simulate the pressure distribution and velocity in the SLM channels, the fluid behavior and SR in the channels were simulated by using computational fluid dynamics. The results of this simulation were then applied to create an empirical model that can be used to predict the SR and material removal thickness. To verify this empirical model, it was applied to an actual part fabricated by SLM. The results were compared with the measurements of the SR and channel diameter subsequent to AFM.

Findings

The proposed model exhibits maximum deviation between the model and the measurement of −1.1% for the down-skin SR, −0.2% for the up-skin SR and −0.1% for material removal thickness.

Practical implications

The results of this study show that the proposed model can avoid expensive iterative tests to determine whether a given channel design leads to the desired SR after smoothing by AFM. Therefore, this model helps to design an AFM-ready channel geometry.

Originality/value

In this paper, a quantitatively validated AFM model was proposed for complex SLM channels with varying orientation angles.

Details

Rapid Prototyping Journal, vol. 26 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 7 October 2020

Yizhi Shao, Oluwamayokun Bamidele Adetoro and Kai Cheng

This study aims to optimize the manufacturing process to improve the manufacturing quality, costs and delivering time with the help of multiscale multiphysics modelling…

Abstract

Purpose

This study aims to optimize the manufacturing process to improve the manufacturing quality, costs and delivering time with the help of multiscale multiphysics modelling and simulation. Multiscale multiphysics-based modelling and simulations are receiving more and more interest by research community and the industry particularly in the context of increasing demands for manufacturing high precision complex products and understanding the intrinsic complexity in associated manufacturing processes.

Design/methodology/approach

In this paper, some modelling and analysis techniques using multiscale multiphysics modelling are presented and discussed.

Findings

Furthermore, the possibility of adopting the multiscale multiphysics modelling and simulation to develop the virtual machining system is evaluated, and further supported with an industrial case study on abrasive flow machining (AFM) of integrally bladed rotors using the techniques and system developed.

Originality/value

With the development of multiscale multiphysics-based modelling and simulation, it will enable effective and efficient optimisation of manufacturing processes and further improvement of manufacturing quality, costs, delivery time and the overall competitiveness.

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Article
Publication date: 9 April 2018

Marco Anilli, Ali Gökhan Demir and Barbara Previtali

The purpose of this paper is to demonstrate the use of selective laser melting for producing single and double chamber laser cutting nozzles. The main aim is to assess a…

Abstract

Purpose

The purpose of this paper is to demonstrate the use of selective laser melting for producing single and double chamber laser cutting nozzles. The main aim is to assess a whole production chain composed of an additive manufacturing (AM) and consecutive finishing processes together. Beyond the metrological and flow-related characterization of the produced nozzles, functional analysis on the use of the produced nozzles are carried out through laser cutting experiments.

Design/methodology/approach

SLM experiments were carried out to determine the correct compensation factor to achieve a desired nozzle diameter on steel with known processibility by SLM and using standard nozzle geometries for comparative purposes. The produced nozzles are finished through electrochemical machining (ECM) and abrasive flow machining (AFM). The performance of nozzles produced via additive manufacturing (AM) are compared to conventional ones on an industrial laser cutting system through cutting experiments with a 6 kW fibre laser. The produced nozzles are characterized in terms of pressure drop and flow dynamics through Schlieren imaging.

Findings

The manufacturing chain was regulated to achieve 1 mm diameter nozzles after consecutive post processing. The average surface roughness could be lowered by approximately 80 per cent. The SLM produced single chamber nozzles would perform similarly to conventional nozzles during the laser cutting of 1 mm mild steel with nitrogen. The double chamber nozzles could provide complete cuts with oxygen on 5 mm-thick mild steel only after post-processing. Post-processing operations proved to decrease the pressure drop of the nozzles. Schlieren images showed jet constriction at the nozzle outlet on the as-built nozzles.

Originality/value

In this work, the use of an additive manufacturing process is assessed together with suitable finishing and functional analysis of the related application to provide a complete production and evaluation chain. The results show how the finishing processes should be allocated in an AM-based production chain in a broader vision. In particular, the results confirm the functionality for designing more complex nozzle geometries for laser cutting, exploiting the flexibility of SLM process.

Details

Rapid Prototyping Journal, vol. 24 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 18 April 2017

Jasgurpreet Singh Chohan and Rupinder Singh

The purpose of this paper is to review the various pre-processing and post-processing approaches used to ameliorate the surface characteristics of fused deposition…

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1715

Abstract

Purpose

The purpose of this paper is to review the various pre-processing and post-processing approaches used to ameliorate the surface characteristics of fused deposition modelling (FDM)-based acrylonitrile butadiene styrene (ABS) prototypes. FDM being simple and versatile additive manufacturing technique has a calibre to comply with present need of tailor-made and cost-effective products with low cycle time. But the poor surface finish and dimensional accuracy are the primary hurdles ahead the implementation of FDM for rapid casting and tooling applications.

Design/methodology/approach

The consequences and scope of FDM pre-processing and post-processing parameters have been studied independently. The comprehensive study includes dominance, limitations, validity and reach of various techniques embraced to improve surface characteristics of ABS parts. The replicas of hip implant are fabricated by maintaining the optimum pre-processing parameters as reviewed, and a case study has been executed to evaluate the capability of vapour smoothing process to enhance surface finish.

Findings

The pre-processing techniques are quite deficient when different geometries are required to be manufactured within limited time and required range of surface finish and accuracy. The post-processing techniques of surface finishing, being effective disturbs the dimensional stability and mechanical strength of parts thus incapacitates them for specific applications. The major challenge for FDM is the development of precise, automatic and controlled mass finishing techniques with low cost and time.

Research limitations/implications

The research assessed the feasibility of vapour smoothing technique for surface finishing which can make consistent castings of customized implants at low cost and shorter lead times.

Originality/value

The extensive research regarding surface finish and dimensional accuracy of FDM parts has been collected, and inferences made by study have been used to fabricate replicas to further examine advanced finishing technique of vapour smoothing.

Details

Rapid Prototyping Journal, vol. 23 no. 3
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 27 March 2009

Zdzislaw Mazur, Rafael Campos‐Amezcua and Alfonso Campos‐Amezcua

This paper aims to validate an axial turbine modified nozzle design, looking for a reduction of the nozzle erosion process during operation in power plants.

Abstract

Purpose

This paper aims to validate an axial turbine modified nozzle design, looking for a reduction of the nozzle erosion process during operation in power plants.

Design/methodology/approach

The approach taken is numerical simulation using the computational fluid dynamics (CFD) tool, comparing original and proposed/modified nozzle designs.

Findings

The paper provides information about how to achieve a solution of the turbine operational problem (abrasive wear) by an analysis of flow patterns under a variety of conditions.

Research limitations/implications

It does not give a detailed interpretation of flow behaviour due to the lack of validation data.

Practical implications

A very useful flow simulation methodology that can be used in industry is provided.

Originality/value

The proposed design modification of an axial turbine nozzle with the aid of CFD simulation has not been performed yet. This paper investigates the possibility of nozzle erosion reduction by modifying local flow patterns.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 19 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 26 July 2021

Ana Pilar Valerga Puerta, J.D. Lopez-Castro, Adrián Ojeda López and Severo Raúl Fernández Vidal

Fused filament fabrication or fused deposition modeling (FFF/FDM) has as one of its main restrictions the surface quality intrinsic to the process, especially linked to…

Abstract

Purpose

Fused filament fabrication or fused deposition modeling (FFF/FDM) has as one of its main restrictions the surface quality intrinsic to the process, especially linked to the layer thickness used during manufacture. The purpose of this paper is to study the possibility of improving the surface quality of polylactic acid (PLA) parts manufactured by FFF using the shot blasting technique.

Design/methodology/approach

The influence of corundum blasting on 0.2 mm layer thickness FDM PLA parts treated with two sizes of abrasive, different exposure times and different incidence pressures.

Findings

As a result, improvements of almost 80% were obtained in the surface roughness of the pieces with high exposure times, and more than 50% in just 20 s.

Originality/value

This technique is cheap, versatile and adaptable to different part sizes and geometries. Furthermore, it is a fast and environmentally friendly technique compared to conventional machining or vapor smoothing. Despite this, no previous studies have been carried out to improve the quality of this technology.

Details

Rapid Prototyping Journal, vol. 27 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

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