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The relationship between the major process variables (laser power, laser scan speed, scan length, beam overlap and Q‐switch pulse frequency) of direct metal laser re‐melting and their effect on the structure of single‐ and multi‐layer copper coupons has been investigated. The work successfully produced selectively fused copper powder layers and simple three‐dimensional copper structures with suitable laser parameters being identified for the production of parts, including thin‐walled cubic structures. It was shown that the specific energy density needed to melt thick powder beds was less than that to melt multi‐layer builds and that the type of substrate material used significantly affected the process parameters. Thus, the substrate and its thermal properties have a significant effect on the melt pool size and freezing rate.

An integral component in heat pipes (HPs) and vapor chambers (VCs) is a porous wicking structure. Traditional methods for manufacturing wicking structures within HPs and VCs involve secondary manufacturing processes and are generally limited to simple geometries. This work aims to leverage the unprecedented level of design freedom of laser powder bed fusion (LPBF) additive manufacturing (AM) to produce integrated wicking structures for HPs and VCs.

Copper wicking structures are fabricated through LPBF via partial sintering and via the formation of square, hexagonal and rectangular arrangements of micro-pins and micro-grooves, produced in multiple build directions. Wicks are characterized by conducting capillary performance analysis through the measurement of porosity, permeability and capillary rate-of-rise.

Copper wicking structures were successfully fabricated with capillary performance, K/reff, ranging from 0.186–1.74 µm. The rectangular-arrangement micro-pin wick presented the highest performance.

This work represents the first published report on LPBF AM of copper wicking structures for HPs/VCs applications and represents foundational knowledge for fabricating complete assemblies of copper VCs and HPs through LPBF AM.

The purpose of this study is to study the mechanical, tribological and electrical properties of the copper-graphene (Cu-Gn) composites fabricated by a novel rapid tooling technique consist of three-dimensional printing and ultrasonic-assisted pressureless sintering (UAPS).

Four different Cu-Gn compositions with 0.25, 0.5, 1 and 1.5 per cent of graphene were fabricated using an amalgamation of three-dimensional printing and UAPS. The polymer 3d printed parts were used to prepare mould cavity and later the UAPS process was used to sinter Cu-Gn powder to acquire free-form shape. The density, hardness, wear rate, coefficient of friction and electrical conductivity were evaluated for the different compositions of graphene and compared with the pure copper. Besides, the comparison was performed with the conventional method.

Cu-Gn composites revealed excellent wear properties due to higher hardness, and the lubrication provided by the graphene. The electrical conductivity of the fabricated Cu-Gn composites started increasing initially but decreased afterwards with increasing the content of graphene. The UAPS fabricated composites outperformed the conventional method manufactured samples with better properties such as density, hardness, wear rate, coefficient of friction and electrical conductivity due to homogeneous mixing of metal particles and graphene.

The fabrication of Cu-Gn composite freeform shapes was found to be difficult using conventional methods. The novel technique using a combination of polymer three-dimensional printing and UAPS as rapid tooling was introduced for the fabrication of freeform shapes of Cu-Gn composites and mechanical, tribological and electrical properties were studied. The method can be used to fabricate optimized complex Cu-Gn structures with improved wear and electrical applications.

Metal-based additive manufacturing is a relatively new technology used to fabricate metal objects within an entirely digital workflow. However, only a small number of different metals are proven for this process. This is partly due to the need to find a new set of parameters which can be used to successfully build an object for every new alloy investigated. There are dozens of variables which contribute to a successful set of parameters and process parameter optimisation is currently a manual process which relies on human judgement.

Here, the authors demonstrate the application of machine learning as an alternative method to determine this set of process parameters, the subject of this test is the processing of pure copper in a laser powder bed fusion printer. Data in the form of optical images were collected over the course of traditional parameter optimisation. These images were segmented and fed into a convolutional autoencoder and then clustered to find the clusters which best represented a high-quality result. The clusters were manually scored according to their quality and the results applied to the original set of parameters.

It was found that the machine-learned clustering and subsequent scoring reflected many of the observations which were found in the traditional parameter optimisation process.

This exercise, as well as demonstrating the effectiveness of the ML approach, indicates an opportunity to fully automate the approach to process optimisation by applying labels to the data, hence, an approach that could also potentially be suited for on-the-fly process optimisation.

This study aims to obtain the mechanistic insights for the fabrication of pure copper thin wall components by selective infrared (IR) laser melting (SLM) and correlated with microstructure development, microhardness, surface morphology and phase analysis. Experimental processes for single track and selection of substrate materials have been studied using a combination of different laser powers and scanning speeds.

SLM of pure copper was performed on a YONGNIAN Laser YLMS-120 SLM machine using an Nd: YAG fiber laser operating at 1,060 nm in the NIR region. Single-track experiments and processing parameters are investigated through different combinations of laser power and scanning speed. The microstructure of the fabricated pure copper samples by SLM technique was analyzed by means of X-ray diffraction, scanning electron microscope equipped with energy disperse spectrometer, optical microscope (OM) and micro-hardness tester.

Steel-based substrates were found suitable for pure copper manufacturing due to sufficient heat accumulation. The width of a single track was determined by liner energy density, showing discontinuities and irregular morphologies at low laser powers and high scanning speeds. As a result of instability of the molten pool induced by Marangoni convection, cracks and cavities were observed to appear along grain boundaries in the microstructure. The top surface morphology of SLM-processed component showed a streamflow structure and irregular shapes. However, the powder particles attached to side surface, which manifest copper powders, are even more sensitive to melt pool of contour track. The crystal phase characteristics of copper components indicated increasing crystallite size of a-Cu, and the decreasing intensity of diffraction peak was attributed to the presence of defects during SLM. The maximum relative density and microhardness were 82 per cent and 61.48 HV0.2, respectively. The minimum thickness of a pure copper thin wall component was 0.2 mm.

This paper demonstrated the forming mechanism and explored feasibility of pure copper thin wall parts by SLM technology in the NIR region. The surface morphology, microstructure and crystal structure were preliminary studied with laser processing parameters.

While international learning programs have received a great deal of attention and have been found to provide valuable learning experiences for participants interested in developing global leadership competencies (GLCs), they are resource-intensive and variably effective. This chapter examines the relatively unexplored use of assessment center (AC) methodology as a complementary avenue for developing students’ GLCs. Scholarly literature sources pertaining to GLCs and their development, experiential learning theory, and AC methodology are reviewed to develop a conceptual model and propositions related to participants’ learning in an AC designed to develop GLCs. An example is described of one university’s design and facilitation of an AC used to develop students’ GLCs. The role of AC methodology, along with international and other learning experiences for developing students’ GLCs, and recommendations for future research, are discussed.

This study aims to examine the relationship between work ethics and organizational performance and investigate the influence of respondents’ career stages on their work ethic among British, United Arab Emirates (UAE) and Serbian nations.

This research is based on a survey of British, UAE and Serbian managers, whose task was to assess the dimensions of the multidimensional work ethic profile (MWEP) and organizational performance. Since the MWEP does not analyze work ethics in the context of religion, it is deemed the most suitable instrument for this study because it analyzes work ethics among the three cultures that practice different religions.

The results revealed that national culture impacts work ethics. British managers place greater value on the wasted time, self-reliance and morality dimensions of work ethics. Serbian managers prefer the leisure and delay of gratification dimensions, while UAE managers value hard work ethics more than the other two groups of managers. The study also shows that respondents’ career stage influences their work ethic, and a significant relationship exists between different dimensions of work ethics and organizational performance in all three nations.

This study contributes to the theory by analyzing work ethic and its relationship with organizational performance and respondents’ career stages in three nations that share business interests. It addresses a research gap by comparing work ethics in developed, developing and a country in socio-economic transition.

Key forces shaping higher education drive institutions to make strategic choices to locate themselves in niches where they can make use of their resources effectively and efficiently. However, the concepts of strategy and strategic positioning in higher education are contested issues due to the nature and complexity of the sector and the university. As an industry facing increasing pressure toward marketization and competition, this study calls for an analysis of higher education, as an industry, in a more business-oriented framework. This chapter makes a contribution to scholarly research in higher education by applying Porter’s five forces framework to medical education. In doing so, it provides a foundational perspective on the competitive landscape, its environment, its organizations, and the groups and individuals that make up the higher and medical education sector.

This paper aims to present a review of extant literature representing attempts to define perceived quality and to propose a new definition. Perceived quality (PQ) is a well-researched, yet vaguely defined subject. Despite a plethora of PQ definitions suggested by various scholars, there is no consensus among researchers on what it really is. The main purpose of this study is to offer a conceptualization of PQ that different researchers and practitioners would agree upon.

This study adopted Garvin's five approaches to defining quality as a frame of reference. The paper utilizes a continuum of approaches to underscore the fact that PQ is neither totally subjective nor wholly objective. After a comprehensive analysis of available conceptualizations, the paper then proposes a new definition that captures the intricate nature of PQ and aligns its various perspectives.

The paper proposes a new definition of PQ as an impression of quality. Such a conceptualization of PQ aligns the various researcher perspectives of it. It also highlights the fact that PQ relies on quality cues under conditions of limited product knowledge by the consumer, a situation known as information asymmetry.

The study contributes to the understanding of the elusive concept of PQ by suggesting a new definition of PQ.

To provide a critique of Belbin's team role theory, including the provision of a re‐definition of the concept of team role and an adequate framework for relating personality to team roles. The re‐defined concept of team roles has a significant social dimension that relates it to the roles people habitually play in teams, the autonomy provided by such roles and their commitment to them. It also advocates the use of the “Big Five” model for describing individual personality differences and relating them to team role behaviour.

A revised model of team role behaviour is described, along with a brief account of the “Big Five” model of personality, and findings are presented that relate team role behaviour to three sets of variables, namely, personality, team role expectations and team role orientation, including autonomy and commitment.

Team role behaviour is described using both self‐assessments and aggregated assessments by others derived from instruments using Likert‐type scales. Information is presented showing the relationship between these measures of team role behaviour and three sets of variables, namely, personality, team role expectations and team role orientation, including autonomy and commitment. These findings support the idea that team roles have a significant social dimension and that the “Big Five” model of personality provides a useful model for relating team role behaviour to individual personality traits.

The research does not look at a number of other issues raised by Belbin's theory of team roles, including the relationship between team composition and team effectiveness. Further research, using the measures described in the article, could be carried out to explore this relationship in actual teams, including exploring team composition in different work contexts.

The main implication of the research is that, while team role behaviour does appear to be related in part to individual personality traits, such traits are much less constraining than Belbin's theory suggests. Team role behaviour can usefully be seen, in part at least, as learned social behaviour, with individuals learning to play different roles in teams. Thus attempts to improve team effectiveness would benefit from looking more at learned behaviour (including leadership, problem solving, work organisation and interpersonal skills, as well as specialist expertise relevant to the particular team), while focusing relatively less on assessment, selection, placement and guidance.

Previous research on, and criticisms of, Belbin's team role theory have challenged it from within the discipline of psychology. This research is unique in criticising it from a more sociological perspective. It is also unique in shifting the practical focus for improving team effectiveness away from assessment, selection, placement and guidance to learned behaviour and skills.