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Article
Publication date: 25 July 2024

Cho-Pei Jiang, Masrurotin Masrurotin, Maziar Ramezani, Alvian Toto Wibisono, Ehsan Toyserkani and Wojciech Macek

Fused deposition modeling (FDM) nowadays offers promising future applications for fabricating not only thermoplastic-based polymers but also composite PLA/Metal alloy materials…

137

Abstract

Purpose

Fused deposition modeling (FDM) nowadays offers promising future applications for fabricating not only thermoplastic-based polymers but also composite PLA/Metal alloy materials, this capability bridges the need for metallic components in complex manufacturing processes. The research is to explore the manufacturability of multi-metal parts by printing green bodies of PLA/multi-metal objects, carrying these objects to the debinding process and varying the sintering parameters.

Design/methodology/approach

Three different sample types of SS316L part, Inconel 718 part and bimetallic composite of SS316L/IN718 were effectively printed. After the debinding process, the printed parts (green bodies), were isothermally sintered in non-vacuum chamber to investigate the fusion behavior at four different temperatures in the range of 1270 °C−1530 °C for 12 h and slowly cooled in the furnace. All samples was assessed including geometrical assessment to measure the shrinkage, characterization (XRD) to identify the crystallinity of the compound and microstructural evolution (Optical microscopy and SEM) to explore the porosity and morphology on the surface. The hardness of each sample types was measured and compared. The sintering parameter was optimized according to the microstructural evaluation on the interface of SS316L/IN718 composite.

Findings

The investigation indicated that the de-binding of all the samples was effectively succeeded through less weight until 16% when the PLA of green bodies was successfully evaporated. The morphology result shows evidence of an effective sintering process to have the grain boundaries in all samples, while multi-metal parts clearly displayed the interface. Furthermore, the result of XRD shows the tendency of lower crystallinity in SS316L parts, whilst IN718 has a high crystallinity. The optimal sintering temperature for SS316L/IN718 parts is 1500 °C. The hardness test concludes that the higher sintering temperature gives a higher hardness result.

Originality/value

This study highlights the successful sintering of a bimetallic stainless steel 316 L/Inconel 718 composite, fabricated via dual-nozzle fused deposition modeling, in a non-vacuum environment at 1500 °C. The resulting material displayed maximum hardness values of 872 HV for SS316L and 755.5 HV for IN718, with both materials exhibiting excellent fusion without any cracks.

Details

Rapid Prototyping Journal, vol. 30 no. 8
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 31 January 2025

Yulius Shan Romario, Chinmai Bhat, Wan-Rong Jiang, I-Chiang Chou, Dao-Yuan Weng, Maziar Ramezani and Cho-Pei Jiang

This study aims to develop a low-cost additive-subtractive hybrid machine equipped with reverse scanning to fabricate high-precision dental surgical guides. The major focus of…

8

Abstract

Purpose

This study aims to develop a low-cost additive-subtractive hybrid machine equipped with reverse scanning to fabricate high-precision dental surgical guides. The major focus of developing the hybrid additive manufacturing technology is to achieve clinical precision of dental tools at an affordable price.

Design/methodology/approach

The designed machine consists of a self-developed vat-photopolymerization-based 3D printer that can fabricate dental surgical guides. The 3D printer is integrated with a self-developed 3D scanner that will analyze the fabricated part and evaluate the dimensional discrepancies. Based on the data provided by the scanner, the integrated secondary milling process will successfully machine the part to meet the clinical precision and standard.

Findings

The efficacy of the newly developed hybrid machine is demonstrated with the fabrication of complex part, lower and upper dental surgical guides with the mean dimensional deviations of 198.1, 136.6 and 117.9 µm, respectively. The integration of the secondary scanning and machining system successfully enhanced the mean dimensional deviation of upper and lower guides by 11.88% and 28.75%, respectively. Furthermore, this study also benchmarked the dimensional accuracies achieved by this low-cost technology with the high-end commercial 3D printers. The overall cost of the machine is evaluated to be $2,399.

Originality/value

This paper proposes a novel hybrid additive manufacturing process with integrated reverse scanning and machining modules to fabricate high-precision dental guides. The developed machine is a low-cost alternative to the existing high-end commercial counterparts. The developed machine has the potential to make endodontic treatments more affordable.

Details

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

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Article
Publication date: 30 July 2019

Huang-Jan Hsu, Shyh-Yuan Lee, Cho-Pei Jiang and Richard Lin

This study aims to compare the marginal fit, flexural strength and hardness for a ceramic premolar that is constructed using dental computer aided machining (CAM) and…

244

Abstract

Purpose

This study aims to compare the marginal fit, flexural strength and hardness for a ceramic premolar that is constructed using dental computer aided machining (CAM) and three-dimensional slurry printing (3DSP).

Design/methodology/approach

Dental CAM and 3DSP are used to fabricate a premolar model. To reduce the fabrication time for 3DSP, a new composition of solvent-free slurry is proposed. Before it is fabricated, the dimensions of the green body for the premolar model are enlarged to account for the shrinkage ratio. A two-stage sintering process ensures accurate final dimensions for the premolar model. The surface morphology of the green body and the sintered premolars that are produced using the two methods is then determined using scanning electronic microscopy. The sintered premolars are seated on a stone model to determine the marginal gap using an optical microscope. The hardness and the flexural strength are also measured for the purpose of comparison.

Findings

The developed solvent-free slurry for 3DSP can be used to produce a premolar green body without micro-cracks or delamination. The maximal marginal gap for the sintered premolar parts that are constructed using the green bodies from dental CAM is 98.9 µm and that from 3DSP is 72 µm. Both methods produce a highly dense zirconia premolar using the same sintering conditions. The hardness value for the dental CAM group is 1238.8 HV, which is slightly higher than that for the 3DSP group (1189.4 HV) because there is a difference in the pre-processing of the initial ceramic materials. However, the flexural strength for 3DSP is 716.76 MPa, which is less than the requirement for clinical use.

Originality/value

This study verifies that 3DSP can be used to fabricate a zirconia dental restoration device that is as good as the one that is produced using the dental CAM system and which has a marginal gap that is smaller than the threshold value. The resulting premolar restoration devices that are produced by sintering the green bodies that are produced using 3DSP and dental CAM under the same conditions have a similar hardness value, which is four times greater than that of enamel. The flexural strength of 3DSP does not meet the requirement for clinical use.

Details

Rapid Prototyping Journal, vol. 25 no. 7
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 12 July 2021

Yong Peng, Yi Juan Luo, Pei Jiang and Peng Cheng Yong

Distribution of long-haul goods could be managed via multimodal transportation networks where decision-maker has to consider these factors including the uncertainty of…

538

Abstract

Purpose

Distribution of long-haul goods could be managed via multimodal transportation networks where decision-maker has to consider these factors including the uncertainty of transportation time and cost, the timetable limitation of selected modes and the storage cost incurred in advance or delay arriving of the goods. Considering the above factors comprehensively, this paper establishes a multimodal multi-objective route optimization model which aims to minimize total transportation duration and cost. This study could be used as a reference for decision-maker to transportation plans.

Design/methodology/approach

Monte Carlo (MC) simulation is introduced to deal with transportation uncertainty and the NSGA-II algorithm with an external archival elite retention strategy is designed. An efficient transformation method based on data-drive to overcome the high time-consuming problem brought by MC simulation. Other contribution of this study is developed a scheme risk assessment method for the non-absolutely optimal Pareto frontier solution set obtained by the NSGA-II algorithm.

Findings

Numerical examples verify the effectiveness of the proposed algorithm as it is able to find a high-quality solution and the risk assessment method proposed in this paper can provide support for the route decision.

Originality/value

The impact of timetable on transportation duration is analyzed and making a detailed description in the mathematical model. The uncertain transportation duration and cost are represented by random number that obeys a certain distribution and designed NSGA-II with MC simulation to solve the proposed problem. The data-driven strategy is adopted to reduce the computational time caused by the combination of evolutionary algorithm and MC simulation. The elite retention strategy with external archiving is created to improve the quality of solutions. A risk assessment approach is proposed for the solution scheme and in the numerical simulation experiment.

Details

Engineering Computations, vol. 39 no. 2
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 17 February 2022

Cho-Pei Jiang, Yung-Chang Cheng, Hong-Wei Lin, Yu-Lee Chang, Tim Pasang and Shyh-Yuan Lee

Polyetheretherketone (PEEK) is used to manufacture biomedical implants because it has a high strength-to-weight ratio and high strength and is biocompatible. However, the use of…

893

Abstract

Purpose

Polyetheretherketone (PEEK) is used to manufacture biomedical implants because it has a high strength-to-weight ratio and high strength and is biocompatible. However, the use of fused deposition modeling to print a PEEK results in low strength and crystallinity. This study aims to use the Taguchi method to optimize the printing factors to obtain the highest tensile strength of the printed PEEK object. The annealing effect on printed PEEK object and crystallinity are also investigated.

Design/methodology/approach

This study determines the printing factors including the printing speed, layer thickness, printing temperature and extrusion width. Taguchi experimental design with a L9 orthogonal array is used to print the tensile specimen and carried out the tensile test to compare the tensile strength and porosity. Analysis of variance (ANOVA) is used to determine the experimental error and to determine the optimization printing parameters to obtain the highest tensile strength. A multivariate linear regression analysis is used to obtain the linear regression equation for predicting the theoretical tensile strength. An X-ray analysis is achieved to evaluate the crystalline of printed object. The effect of annealing is investigated to improve the tensile strength of printed part. An intervertebral lumber device is printed to demonstrate the feasibility of the obtained optimization parameters for practical application.

Findings

Taguchi experiment designs nine sets of parameters to print the PEEK tensile specimen. The experimental results and the ANOVA present that the order in which the factors affect the tensile strength for printed PEEK parts is the layer thickness, the extrusion width, the printing speed and the printing temperature. The optimized printing parameters are a printing speed of 5 mm/s, a layer thickness of 0.1 mm, a printing temperature of 395 °C and an extrusion strand width of 0.44 mm. The average tensile strength of printed specimen with the optimized printing parameters is 91.48 MPa, which is slightly less than the theoretical predicted value of 94.34 MPa. After annealing, the tensile strength increases to 98.85 MPa, which is comparable to that for molded PEEK and the porosity decreases to 0.3 from 3.9%. X-ray diffraction results show that all printed and annealed specimens have a high degree of crystallinity. The printed intervertebral lumber device has ultimate compressive load of 13.42 kN.

Originality/value

The optimized printing parameters is suitable for low-price fused deposition modeling machine because it does not involve a table at high temperature and can print the PEEK object with high tensile strength and good crystalline. Annealing parameters offer a good solution for tensile strength improvement.

Details

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

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Article
Publication date: 2 January 2018

Wei-Ting Chang, Huang-Jan Hsu, Cho-Pei Jiang, Shyh-Yuan Lee and Yuan-Min Lin

The aim of this paper is to examine the effects of light controlling system that combined high refractive particles (n-TiO2 [titanium dioxide – TiO2]) and tartrazine lake dye (TL…

224

Abstract

Purpose

The aim of this paper is to examine the effects of light controlling system that combined high refractive particles (n-TiO2 [titanium dioxide – TiO2]) and tartrazine lake dye (TL dye) on thickness, flexural strength, flexural modulus and surface details of the 3D-printed resin.

Design/methodology/approach

Influences of different concentrations of n-TiO2 and TL dye in light-cured resin formulations for 3D printing (3DP) application were evaluated, including curing thickness, flexural strength and surface details under scanning electron microscopy.

Findings

The polymerization thickness of samples containing both n-TiO2 and TL dye was lower compared to samples with TL dye solely. Samples containing more n-TiO2 and more TL dye exhibited lower flexural strength and modulus. Ramp models showed that for samples containing 1 per cent TL dye, when their n-TiO2 content increased from 1 to 5 per cent, surface laminate structures became sharper. However, when the TL dye content doubled to 2 per cent, the surface laminate structures were indefinite compared to 1 per cent TL dye-containing counterparts.

Originality value

In visible-light 3DP, light controlling system in cooperate dye with high refractive particles provides better energy distribution and scattering control. High refractive particles, dyes and light exposure time had influenced the surface resolution and mechanical properties of the 3DP products.

Details

Rapid Prototyping Journal, vol. 24 no. 1
Type: Research Article
ISSN: 1355-2546

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Publication date: 29 September 2021

Emanuel Gomes, Sunbir Alam and Qile He

Over the last few decades, management has witnessed a proliferation of research on mergers and acquisitions (M&As) and strategic alliances (SAs). Although both fields have been…

Abstract

Over the last few decades, management has witnessed a proliferation of research on mergers and acquisitions (M&As) and strategic alliances (SAs). Although both fields have been widely studied, the relationship between the two bodies of literature has not been sufficiently explored. Despite the enormous commonality between both phenomena in terms of the drivers behind them and of the critical success factors associated with the M&A and alliance process management, scholars from the two fields have rarely exchanged findings and insights, even though they may be highly relevant to each other. M&A and SA research remain mostly separated from each other, thus minimizing the ability for more mutually beneficial complementary and synergetic knowledge sharing effects.

This chapter synthesizes and compares existing theoretical perspectives from the M&A and SA literatures and identifies opportunities for future research and knowledge cross fertilization between the two fields. Building upon previous review studies about M&A and SA literatures, the authors develop a comparative longitudinal review of both literatures published in top management journals over a 27-year period. For that purpose, the authors resort to machine learning algorithms to discover thematic patterns that may have gone unnoticed by using traditional review methods.

By highlighting some of the shortcomings that limit the authors’ theoretical and practical understandings, they challenge scholars from both fields (M&A and SA) to go beyond what they think they know from compartmentalized received theory, and draw upon novel and meaningful ideas, concepts, and theoretical approaches from “the other side of the fence.” The authors believe that such a dialog will facilitate further theoretical exploration and empirical investigation of both phenomena and produce insights that will influence the practical management of M&A and SAs.

Available. Open Access. Open Access
Article
Publication date: 13 September 2022

Gafar Abdalkrim and Moncef Guizani

This study investigates the effect of strategic internal critical factors on strategic alliance performance in an emerging market, the Kingdom of Saudi Arabia.

2009

Abstract

Purpose

This study investigates the effect of strategic internal critical factors on strategic alliance performance in an emerging market, the Kingdom of Saudi Arabia.

Design/methodology/approach

Multivariate statistical analysis technique Partial Least Square-Squared Equation Model is used for data analysis considering a survey of 260 alliance managers.

Findings

Environmental complexity moderates the relationship between strategic internal critical factors and strategic performance. A significant positive effect of strategic internal critical factors on corporation strategic performance was found. It suggests that environment and strategic alliance enable alliance managers and decision-makers to translate alliance strategies and improve the overall organization’s performance outcome, productivity, efficiency, availability of a product and profitability.

Practical implications

The findings disseminate beneficial implications for alliance managers regarding how they can best use their capability to maximize alliance performance. Realizing the antecedents of strategic alliance performance allows a manager to be sensitive about the influent factors and try to improve the alliance performance.

Originality/value

This paper shows how to create associations between interfirm coordination as a framework of new ventures for implementing radical technological change, firm performance in the post-innovation period, industry and firm innovative output.

Details

Arab Gulf Journal of Scientific Research, vol. 40 no. 4
Type: Research Article
ISSN: 1985-9899

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Article
Publication date: 4 June 2020

Wan Chen and Longwei Wang

This paper aims to investigate how firm-level factor entrepreneurial orientation affects alliance outcomes, and how two sources of uncertainty – competitive intensity and the…

538

Abstract

Purpose

This paper aims to investigate how firm-level factor entrepreneurial orientation affects alliance outcomes, and how two sources of uncertainty – competitive intensity and the dependence of an entrepreneurially oriented firm on its partner – moderate the relationship between entrepreneurial orientation and alliance performance.

Design/methodology/approach

The hypotheses are tested using survey data from 196 R&D alliances in China.

Findings

The results indicate that the relationship between entrepreneurial orientation and alliance performance has an inverted U shape and is negatively moderated by competitive intensity and the entrepreneurial orientation firm’s dependence on its partner.

Practical implications

Entrepreneurial orientation can have positive and negative effects on alliance performance. Particularly in contexts of intense competition or dependence on partners, firms with an entrepreneurial orientation must fully exploit the advantage this brings them, improve their self-control and alliance-coordination capabilities and emphasize the joint effects of technological innovation and market factors on new product development in case of alliance failure.

Originality/value

This study highlights the dual role of entrepreneurial orientation in R&D alliances. By incorporating external and internal sources of uncertainty (competitive intensity and dependence on the partner), it also offers a more comprehensive understanding of how different levels of entrepreneurial orientation affect R&D alliance performance.

Details

Journal of Business & Industrial Marketing, vol. 35 no. 12
Type: Research Article
ISSN: 0885-8624

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Article
Publication date: 10 July 2020

Ribin Seo

Despite increasing research on the social nature of entrepreneurial collaboration in the context of alliances, its performance implication has been under debate. The present study…

544

Abstract

Purpose

Despite increasing research on the social nature of entrepreneurial collaboration in the context of alliances, its performance implication has been under debate. The present study tests a theoretical framework to elucidate the mediated relationship between social capital (SC) and research and development (R&D) alliance performance through the entrepreneurial orientation (EO) of alliance firms.

Design/methodology/approach

Based on the authors’ literature review, SC is conceptualized as the sum of actual and potential assets, including structural, relational and cognitive capital, embedded within the networks of alliance partners. Alliance performance is regarded as a combination of technological performance and business performance, corresponding to the mutual and private benefits of R&D alliances, respectively. This study hypothesizes the potential impact of SC on alliance performance and the mediating role of EO in the relationship.

Findings

The results from an analysis of 218 Korean ventures that participated in R&D alliance projects as focal alliance partners show that each SC dimension drives alliance firms to enact EO, which eventually leads to increased performance in technology and business. Specifically, EO contributes to translating the implications of SC for technological performance partially and for business performance completely.

Originality/value

This study links fragmented theoretical perspectives in research, shedding new light on the importance of social nature in the context of R&D alliances, which conditions entrepreneurial collaboration for better alliance performance. The findings suggest that practitioners should adopt an ambidextrous approach to the SC–EO interface at the alliance level, which opens a gateway to achieve greater performance by alliance.

Details

International Journal of Entrepreneurial Behavior & Research, vol. 26 no. 6
Type: Research Article
ISSN: 1355-2554

Keywords

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