Athanasios Goulas and Ross J. Friel
The purpose of this paper is to investigate the effect of the main process parameters of laser melting (LM) type additive manufacturing (AM) on multi-layered structures…
Abstract
Purpose
The purpose of this paper is to investigate the effect of the main process parameters of laser melting (LM) type additive manufacturing (AM) on multi-layered structures manufactured from JSC-1A Lunar regolith (Moondust) simulant powder.
Design/methodology/approach
Laser diffraction technology was used to analyse and confirm the simulant powder material particle sizes and distribution. Geometrical shapes were then manufactured on a Realizer SLM™ 100 using the simulant powder. The laser-processed samples were analysed via scanning electron microscopy to evaluate surface and internal morphologies, X-ray fluorescence spectroscopy to analyse the chemical composition after processing, and the samples were mechanically investigated via Vickers micro-hardness testing.
Findings
A combination of process parameters resulting in an energy density value of 1.011 J/mm2 allowed the successful production of components directly from Lunar regolith simulant. An internal relative porosity of 40.8 per cent, material hardness of 670 ± 11 HV and a dimensional accuracy of 99.8 per cent were observed in the fabricated samples.
Originality/value
This research paper is investigating the novel application of a powder bed fusion AM process category as a potential on-site manufacturing approach for manufacturing structures/components out of Lunar regolith (Moondust). It was shown that this AM process category has the capability to directly manufacture multi-layered parts out of Lunar regolith, which has potential applicability to future moon colonization.
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Ji Li, Tom Monaghan, Robert Kay, Ross James Friel and Russell Harris
This paper aims to explore the potential of ultrasonic additive manufacturing (UAM) to incorporate the direct printing of electrical materials and arrangements (conductors and…
Abstract
Purpose
This paper aims to explore the potential of ultrasonic additive manufacturing (UAM) to incorporate the direct printing of electrical materials and arrangements (conductors and insulators) at the interlaminar interface of parts during manufacture to allow the integration of functional and optimal electrical circuitries inside dense metallic objects without detrimental effect on the overall mechanical integrity. This holds promise to release transformative device functionality and applications of smart metallic devices and products.
Design/methodology/approach
To ensure the proper electrical insulation between the printed conductors and metal matrices, an insulation layer with sufficient thickness is required to accommodate the rough interlaminar surface which is inherent to the UAM process. This in turn increases the total thickness of printed circuitries and thereby adversely affects the integrity of the UAM part. A specific solution is proposed to optimise the rough interlaminar surface through deforming the UAM substrates via sonotrode rolling or UAM processing.
Findings
The surface roughness (Sa) could be reduced from 4.5 to 4.1 µm by sonotrode rolling and from 4.5 to 0.8 µm by ultrasonic deformation. Peel testing demonstrated that sonotrode-rolled substrates could maintain their mechanical strength, while the performance of UAM-deformed substrates degraded under same welding conditions ( approximately 12 per cent reduction compared with undeformed substrates). This was attributed to the work hardening of deformation process which was identified via dual-beam focussed ion beam–scanning electron microscope investigation.
Originality/value
The sonotrode rolling was identified as a viable methodology in allowing printed electrical circuitries in UAM. It enabled a decrease in the thickness of printed electrical circuitries by ca. 25 per cent.
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This paper aims to comprehensively review ultrasonic additive manufacturing (UAM) process history, technology advancements, application areas and research areas. UAM, a hybrid 3D…
Abstract
Purpose
This paper aims to comprehensively review ultrasonic additive manufacturing (UAM) process history, technology advancements, application areas and research areas. UAM, a hybrid 3D metal printing technology, uses ultrasonic energy to produce metallurgical bonds between layers of metal foils near room temperature. No melting occurs in the process – it is a solid-state 3D metal printing technology.
Design/methodology/approach
The paper is formatted chronologically to help readers better distinguish advancements and changes in the UAM process through the years. Contributions and advancements are summarized by academic or research institution following this chronological format.
Findings
This paper summarizes key physics of the process, characterization methods, mechanical properties, past and active research areas, process limitations and application areas.
Originality/value
This paper reviews the UAM process for the first time.
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Neil Wilson, Michael Ross, Kevin Lafferty and Russell Jones
The concept of utilising greenspace to promote and maintain mental health predates the development of almost all current treatment modalities. Although the use of greenspace as a…
Abstract
The concept of utilising greenspace to promote and maintain mental health predates the development of almost all current treatment modalities. Although the use of greenspace as a therapeutic tool decreased throughout the 20th century, research in this area has grown exponentially over the last 20 years. This review examines the theory and increasing evidence base behind the psychological, social and physical health benefits of viewing and interacting with greenspace, and considers some of the common methodological limitations within the literature.Those who use secondary and tertiary care mental health services typically experience secondary problems due to reduced levels of social and physical activity. This review argues that the holistic benefits of greenspace make ecotherapy particularly appropriate for such a population. The review recommends that the effects of ecotherapy on those who use secondary and tertiary mental health care services be explored as part of an effort to redress the absence in the literature of quality studies in this area for this population.
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Data literacy – the ability to read, analyze, interpret, evaluate and argue with data and data visualizations – is an essential competency in social studies. This study aims to…
Abstract
Purpose
Data literacy – the ability to read, analyze, interpret, evaluate and argue with data and data visualizations – is an essential competency in social studies. This study aims to examine the degree to which US state standards require teachers to teach data literacy in social studies, addressing the questions: to what extent are US social studies teachers required to teach data literacy? If they are required to teach it, are they provided with guidance about competencies to address at each school or grade level and with respect to particular content?
Design/methodology/approach
The study used content analysis, using a variety of priori and emergent codes, to review social studies standards documents from all 50 states and the District of Columbia.
Findings
Findings indicate that although state standards suggest that data visualizations should play a role in social studies instruction, they provide poor guidance for a coherent, progressive and critical approach across grade levels.
Originality/value
Researchers currently know little about if and how teachers address data literacy in social studies education. This study provides a snapshot of guidance teachers across states are given for teaching data literacy, and by extension, the quality of data literacy instruction recommended for students across the USA.
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V. Raja Sreedharan and R. Raju
The purpose of this paper is to review Lean Six Sigma (LSS) literature and report different definitions, demographics, methodologies and industries.
Abstract
Purpose
The purpose of this paper is to review Lean Six Sigma (LSS) literature and report different definitions, demographics, methodologies and industries.
Design/methodology/approach
This paper highlights various definitions by different researchers and practitioners. A total of 235 research papers has been reviewed for the LSS theme, research methodology adopted, type of industry, author profile, country of research and year of publication.
Findings
From the review, four significant LSS classifications were identified that deal with the spread of LSS in different industries followed by observation for classification.
Practical implications
LSS is a strategy for success, but it did not examine its presence in various Industries. From this paper, readers can understand the quantum of its spread before implementing LSS. For academicians, it will be a comprehensive list of papers for research.
Originality/value
This paper reviews 235 research papers for their year, author profile, research methodology and type of industry. Various characteristics of LSS definitions and their theme are also reviewed.