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1 – 10 of 245Abhishek Shrivastava, Anand Kumar S. and Samrat Rao
This study used an indentation-based mechanical testing framework for the mechanical characterization of laser powder bed fusion (LPBF) processed Inconel 718 on a wrought Inconel…
Abstract
Purpose
This study used an indentation-based mechanical testing framework for the mechanical characterization of laser powder bed fusion (LPBF) processed Inconel 718 on a wrought Inconel 718 substrate. The purpose of the paper is to investigate the effectiveness of the indentation-based approach for localized mechanical evaluation.
Design/methodology/approach
The LPBF-processed wrought substrate was sectioned into three sections for microstructural and mechanical characterization. A 3D heat source model was used for the thermal analysis of the interface region. The developed interface region is probed using the Knoop hardness indenter in different orientations to determine the textural anisotropy and mechanical behavior of the region.
Findings
LPBF process develops a melted interface zone (MIZ) at the deposition-substrate interface. The MIZ exhibited a coarse grain structure region along with a larger primary dendritic arm spacing (PDAS), signifying a slower cooling rate. FE modeling of the LPBF process reveals heat accumulation in the substrate along with intrinsic heat treatment (IHT) induced due to layer-wise processing. The obtained yield locus shows strong anisotropy in the deposition region, whereas reduced anisotropy with a nearly uniform ellipse locus for the MIZ regions. This reduced anisotropy is attributable to IHT and heat accumulation in the substrate.
Originality/value
An alternative localized mechanical characterization tool has been investigated in this work. The approach proved sensitive to thermal variations during LPBF processing in an isolated region which extends its suitability to variable geometry parts. Moreover, the approach could serve as a screening tool for parts made from dissimilar metals.
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Jiacheng Zhou, Jinglin Shi, Lei Xu, Fuwen Zhang, Zhigang Wang, Qiang Hu and Huijun He
The reliability of solder joints is closely related to the growth of an intermetallic compound (IMC) layer between the lead-free solder and substrate interface. This paper aims to…
Abstract
Purpose
The reliability of solder joints is closely related to the growth of an intermetallic compound (IMC) layer between the lead-free solder and substrate interface. This paper aims to investigate the growth behavior of the interfacial IMC layer during isothermal aging at 125°C for Sn-3Ag-3Sb-xIn/Cu (x = 0, 1, 2, 3, 4, 5 Wt.%) solder joints with different In contents and commercial Sn-3Ag-0.5Cu/Cu solder joints.
Design/methodology/approach
In this paper, Sn-3Ag-3Sb-xIn/Cu (x = 0, 1, 2, 3, 4, 5 Wt.%) and commercial Sn-3Ag-0.5Cu/Cu solder were prepared for bonding Cu substrate. Then these samples were subjected to isothermal aging for 0, 2, 8, 14, 25 and 45 days. Scanning electron microscopy and transmission electron microscopy were used to analyze the soldering interface reaction and the difference in IMC growth behavior during the isothermal aging process.
Findings
When the concentration of In in the Sn-3Ag-3Sb-xIn/Cu solder joints exceeded 2 Wt.%, a substantial amount of InSb particles were produced. These particles acted as a diffusion barrier, impeding the growth of the IMC layer at the interface. The growth of the Cu3Sn layer during the aging process was strongly correlated with the presence of In. The growth rate of the Cu3Sn layer was significantly reduced when the In concentration exceeded 3 Wt.%.
Originality/value
The addition of In promotes the formation of InSb particles in Sn-3Ag-3Sb-xIn/Cu solder joints. These particles limit the growth of the total IMC layer, while a higher In content also slows the growth of the Cu3Sn layer. This study is significant for designing alloy compositions for new high-reliability solders.
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Jinshuai Xie, Lei Tang, Pengfei Gao, Zhengquan Zhang and Liangfeng Li
This paper aims to study the effect of different Ni content on the microstructure and properties of Sn-0.7Cu alloy. Then, the spreading area, wetting angle, interface layer…
Abstract
Purpose
This paper aims to study the effect of different Ni content on the microstructure and properties of Sn-0.7Cu alloy. Then, the spreading area, wetting angle, interface layer thickness and microstructure of the soldering interface was observed and analyzed at different soldering temperatures and times.
Design/methodology/approach
Sn-0.7Cu-xNi solder alloy was prepared by a high-frequency induction melting furnace. Then Sn-0.7Cu-xNi alloy was soldered on a Cu substrate at different soldering temperatures and times.
Findings
It was found that Ni made the intermetallic compounds in the Sn-0.7Cu solder alloy gradually aggregate and coarsen, and the microstructure was refined. The phase compositions of the solder alloy are mainly composed of the ß-Sn phase and a few intermetallic compounds, Cu6Sn5 + (Cu, Ni)6Sn5. The maximum value of 12.1 HV is reached when the Ni content is 0.1 Wt.%. When the Ni content is 0.5 Wt.%, the wettability of the solder alloy increases by about 15%, the interface thickness increases by about 8.9% and the scallop-like structure is the most refined. When the soldering time is 10 min and the soldering temperature is 280 °C, the wettability of Sn-0.7Cu-0.2Ni is the best.
Originality/value
It is groundbreaking to combine the change in soldering interface with the soldering industry. The effects of different soldering temperatures and times on the Sn-0.7Cu-xNi alloy were studied. Under the same conditions, Sn-0.7Cu-0.2Ni exhibits better wettability and more stable solder joint stability.
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This study aims to explore the synthesis, characteristics and utilization of polymer composites integrated with cutting-edge pigments.
Abstract
Purpose
This study aims to explore the synthesis, characteristics and utilization of polymer composites integrated with cutting-edge pigments.
Design/methodology/approach
The incorporation of advanced pigments introduces functionalities such as enhanced mechanical strength, thermal stability, ultraviolet resistance and color stability, thus extending the range of applications in diverse fields including automotive, aerospace, electronics and construction.
Findings
This review discusses the mechanisms underlying the property enhancements achieved through the incorporation of advanced pigments and highlights recent developments in the field.
Originality/value
Polymer composites incorporating advanced pigments have garnered significant attention in recent years because of their potential to enhance various material properties and broaden their applications. This paper explores the fabrication methods of polymer composites reinforced with organic/inorganic advanced pigments in brief along with their characteristics and applications.
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Amirul Syafiq, Lilik Jamilatul Awalin, Syukri Ali and Mohd Arif
The paper aims to design the optimum formulation of the nano-titanium dioxide (TiO2) hydrophilic coating system using the synthetic polypropylene glycol (PPG), which can create…
Abstract
Purpose
The paper aims to design the optimum formulation of the nano-titanium dioxide (TiO2) hydrophilic coating system using the synthetic polypropylene glycol (PPG), which can create the reflection and absorption property.
Design/methodology/approach
TiO2 nanoparticles are used as fillers, and PPG has been blended at the proper ratio of 1PPG: 0.2TiO2. The prepared resin has been applied onto the glass substrate at different numbers of glass immersions during the dip-coating fabrication process. One-time glass immersion is labeled as T1 coating, two-time glass immersion is labeled as T2 coating and three-time glass immersion is labeled as T3 coating. All the prepared coating systems were left dry at ambient temperature.
Findings
T3 coating showed the lowest reading of WCA value at 40.50°, due to higher surface energy at 61.73 mN/m. The T3 coating also shows the greatest absorbance property among the prepared coating systems among the prepared coating. In terms of reflectance property, the T2 coating system has great reflectance in UV region and near-infrared region, which is 16.47% and 2.77 and 2.73%, respectively. The T2 coating also has great optical transmission about 75.00% at the visible region.
Research limitations/implications
The development of thermal insulation coating by studying the relationship between convection heat and reflectance at different wavelengths of incident light.
Practical implications
The developed coating shows high potential for glass window application.
Originality/value
The application of the hydrophilic coating on light absorption, reflectance and transmission at different wavelengths.
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Jonathan G. Ercanbrack and Ali Ali
This study aims to examine the extent to which traditional juristic approaches to determining intention in Islamic law are altered in the institutional framework and…
Abstract
Purpose
This study aims to examine the extent to which traditional juristic approaches to determining intention in Islamic law are altered in the institutional framework and standard-setting project of the Malaysian state.
Design/methodology/approach
The study used the transnational law theory, which views normativity as culturally, socially and religiously embedded. The development of norms, customs and laws is also contingent on self-maximizing behavior. The Sharīʿa Advisory Council’s interpretation of the bayʿ al-ʿīnah standard is a case study of this approach to the development of law.
Findings
This study shows that traditional approaches to determining the validity of an Islamic contract have been displaced by the institutional logic of the state, which prioritizes uniformity and certainty in law and reflects liberal, Western and capitalistic values. Islamic standard setting is part of the state’s objective to uniformize law due to the globalization of financial markets. The normative collisions in the standard-setting project produce a new jurisprudence based on the state’s uniform and purposive determination of a contract’s validity.
Research limitations/implications
Further research on institutional frameworks is needed to conceptualize how Islamic commercial principles and ethics can be incentivized in the state’s legal systems.
Originality/value
Few works, if any, have examined the interaction of the state’s institutional environment with jurists’ traditional approaches to determining contractual intention. Most scholarship assumes the decisive role of market forces, but the role of law and institutions in this context is under-researched.
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Chithra V.P., Balaji Bakthavatchalam, Jayakumar J.S., Khairul Habib and Sambhaji Kashinath Kusekar
This paper aims to present a comprehensive analysis of conjugate heat transfer phenomena occurring within the developing region of square ducts under both isothermal and isoflux…
Abstract
Purpose
This paper aims to present a comprehensive analysis of conjugate heat transfer phenomena occurring within the developing region of square ducts under both isothermal and isoflux boundary conditions. The study involves a rigorous numerical investigation, using advanced computational methods to simulate the complex heat exchange interactions between solid structures and surrounding fluid flows. The results of this analysis provide valuable insights into the heat transfer characteristics of such systems and contribute to a deeper understanding of fluid–thermal interactions in duct flows.
Design/methodology/approach
The manuscript outlines a detailed numerical methodology, combining computational fluid dynamics and finite element analysis, to accurately model the conjugate heat transfer process. This approach ensures both the thermal behaviour of the solid walls and the fluid flow dynamics are well captured.
Findings
The results presented in the manuscript reveal significant variations in heat transfer characteristics for isothermal and isoflux boundary conditions. These findings have implications for optimizing heat exchangers and enhancing thermal performance in various engineering applications.
Practical implications
The insights gained from this study have the potential to influence the design and optimization of heat exchange systems, contributing to advancements in energy efficiency and engineering practices.
Originality/value
The research introduces a novel approach to study conjugate heat transfer in square ducts, particularly focusing on the developing region. This unique perspective offers fresh insights into heat transfer mechanisms that were previously not thoroughly explored.
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Fatma Bouzeboudja and Abdelmadjid Si Salem
To contribute to the identification of the parameters influencing the behavior of textile-reinforced concrete (TRC), the purpose of this paper is to investigate the flexural…
Abstract
Purpose
To contribute to the identification of the parameters influencing the behavior of textile-reinforced concrete (TRC), the purpose of this paper is to investigate the flexural behavior of TRC-based plates under four-point bending notably designed in the context of sustainable development and the substitution of mortar components with natural and abundant materials.
Design/methodology/approach
An extensive experimental campaign was focused about two main parameters. The first one emphases the textile reinforcements, such as the number of layers, the nature and the textile mesh size. In the second step, the composition of the mortar matrix was explored through the use of dune sand as a substitute of the river one.
Findings
Test results in terms of load-displacement response and failure patterns were highlighted, discussed and confronted to literature ones. As key findings, an increase of the load-bearing capacity and ductility, comparable to the use of an industrially produced second textile layer was recorded with the use of dune sand in the mortar mix design. The designed ecofriendly samples with economic concerns denote the significance of obtained outcomes in this research study.
Originality/value
The novelty of the present work was to valorize the use of natural dune sand to design new TRC samples to respond to the environmental and economical requirements. The obtained values provide an improved textiles–matrix interface performance compared to classical TRC samples issued from the literature.
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Panagiota Polydoropoulou, Leonardo Cosma, George Labeas, Dionysios Markatos, Rosario Dotoli and Francesca Felline
This paper aims to use two different numerical approaches to simulate the induction welding process for a hybrid thermoplastic material, and the results have been validated…
Abstract
Purpose
This paper aims to use two different numerical approaches to simulate the induction welding process for a hybrid thermoplastic material, and the results have been validated experimentally.
Design/methodology/approach
The first approach used a numerical model that combines electromagnetism, heat transfer and solid mechanics in the same numerical environment using Hexagon Marc software. Simultaneously, a computationally efficient approach combined steady-state electromagnetism results at specific intervals in the Ansys EM suite with heat transfer and solid mechanics in Ansys Workbench.
Findings
The results from both numerical approaches showed a strong correlation with the experimental findings.
Originality/value
The current research offers valuable insights into enhancing induction welding procedures within the aerospace industry, as well as across broader industrial applications. The synergistic combination of numerical simulations and experimental validation served as a robust framework for future research endeavors aimed at enhancing the efficiency, reliability and quality of thermoplastic welding techniques.
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Jochen Fähndrich and Burkhard Pedell
This study aims to analyse the influence of digitalisation on the management control function of small and medium-sized enterprises (SMEs). In particular, it aims to illuminate…
Abstract
Purpose
This study aims to analyse the influence of digitalisation on the management control function of small and medium-sized enterprises (SMEs). In particular, it aims to illuminate how digitalisation influences management control elements, organisation and roles/competencies and to identify obstacles to digitalisation of management control in SMEs and measures taken to overcome them.
Design/methodology/approach
The study is based on guideline-supported expert interviews conducted with 14 financial managers from SMEs in Germany, Austria and Switzerland.
Findings
This study reveals the influence of digitalisation on management control elements, organisation, and roles/competencies. The automation and standardisation of management control processes result in new elements for management control, such as strategic support for management. In addition, the increased availability and transparency of data enable the use of instruments within a company that allow for quick analyses of the company's development. Digitalisation leads to the integration of management control into the corporate network and, thus, a change in the organisation of management control. It also triggers the expansion of management control competencies, especially IT competencies. A shortage of internal digitalisation resources, unclear corporate roadmaps, and a lack of managerial experience loom as central challenges for digitalising the management control function. Measures derived from the interviews can help SMEs overcome the obstacles to the digitalisation of management control.
Originality/value
This research is the first interview-based study of the impact of digitalisation on management control in SMEs, potential obstacles to that digitalisation, and measures to overcome those obstacles. Thus, it contributes to the emerging debate on factors that may explain why SMEs lag in terms of the digitalisation of their internal processes.
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