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The ability to use laser powder bed fusion (LPBF) to print parts with tailored surface topography could reduce the need for costly post-processing. However, characterizing the as-built surface topography as a function of process parameters is crucial to establishing linkages between process parameters and surface topography and is currently not well understood. The purpose of this study is to measure the effect of different LPBF process parameters on the as-built surface topography of Inconel 718 parts.

Inconel 718 truncheon specimens with different process parameters, including single- and double contour laser pass, laser power, laser scan speed, build orientation and characterize their as-built surface topography using deterministic and areal surface topography parameters are printed. The effect of both individual process parameters, as well as their interactions, on the as-built surface topography are evaluated and linked to the underlying physics, informed by surface topography data.

Deterministic surface topography parameters are more suitable than areal surface topography parameters to characterize the distinct features of the as-built surfaces that result from LPBF. The as-built surface topography is strongly dependent on the built orientation and is dominated by the staircase effect for shallow orientations and partially fused metal powder particles for steep orientations. Laser power and laser scan speed have a combined effect on the as-built surface topography, even when maintaining constant laser energy density.

This work addresses two knowledge gaps. (i) It introduces deterministic instead of areal surface topography parameters to unambiguously characterize the as-built LPBF surfaces. (ii) It provides a methodical study of the as-built surface topography as a function of individual LPBF process parameters and their interaction effects.

The increased use cases for laser powder bed fusion (LPBF) in the research and commercial domains necessitate a better understanding of the inputs and the processing parameters. Porosity in parts manufactured by LPBF could lead to premature failure and increased cost. The powder bed, which is selectively laser melted, must be as densely packed as possible to ensure high-density parts. This paper aims to identify and qualify the variables that affect the packing density of the powder bed.

Six different independent variables that affect the packing density of the powder were identified and quantified. The chemical composition, true powder density, powder size distribution, powder circularity and convexity and powder morphology were studied. A powder bed density capsule was printed in place to determine the actual powder bed density in the LPBF unit.

Particle size destitution is the most critical aspect of the packing density in the LPBF unit. Powder with better circularity, convexity and higher powder density has proven to pack less densely than powder with many smaller particles. A more significant number of fine particles will ensure the voids between larger particles are filled, and a denser item, with less porosity, can be manufactured.

The independent variables quantified in this study to determine their effect on the packing densities are discussed. Adherence to the ASTM standard applicable to this industry is discussed, and the quantification method is evaluated. This work’s original contribution is identifying the effect of the ratio of D₉₀ to D₁₀ values based on particle diameter and its interaction within the LPBF unit to result in the highest possible packing density.

In the present study, a steel lifting lug is replaced with a composite (carbon fiber-reinforced epoxy [CFRP]) lifting lug made of a carbon/epoxy composite. The purpose of this paper was to obtain a composite lifting lug with a higher level of strength that is capable of carrying loads without failure.

The vibration and static behaviors of steel and composite lifting lugs have been investigated using finite element analysis (FEA), ANSYS software. The main consideration in the design of the composite (CFRP) lifting lug was that the displacement of both steel and composite lugs was the same under the same load. Hence, by using the FEA displacement result of the steel lifting lug, the thickness of the composite lifting lug is determined using FEA.

Compared to the steel lifting lug, the composite (CFRP) lifting lug has much lower stresses and much higher natural frequencies. Static behavior was experienced by the composite lifting lug, showing a reduction in von Mises stress, third principal stress and XZ shear stress, respectively, by 48.4%, 34.6% and 89.8%, respectively, when compared with the steel lifting lug. A higher natural frequency of mode shape swaying in X (258.976√1,000 Hz) was experienced by the composite lifting lug when compared to the steel lifting lug (195.935√1,000 Hz). The safe strength of the design composite lifting lug has been proven by FEA results, which showed that the composite (CFRP) lifting lug has a higher factor of safety in all developed stresses than the steel lifting lug. According to von Mises stress, the factor of safety of the composite lifting lug is increased by 76% when compared to the steel lifting lug. The von Mises stress at the edge of the hole in the composite lifting lug is reduced from 23.763 MPa to 20.775 MPa when compared to the steel lifting lug.

This work presents the designed composite (CFRP) lifting lug, which will be able to carry loads with more safety than a steel one.

This study aims to explore the intention to quit and its associations among ambulance personnel and to compare the intention to quit and its associations between paramedic and non-paramedic staff.

A cross-sectional study was conducted on 492 Australian ambulance personnel. Participants were selected by stratified random sampling. Data were collected using phone interview-administered questionnaires. Descriptive analyses, bivariate associations and structural equation modelling were performed for data analysis.

The study found that 70% of ambulance personnel intended to quit their jobs. Intention to quit was similar between paramedics and non-paramedic staff. In both staff groups, supervisors' and colleagues' support was associated with mental health symptoms; job satisfaction was associated with the intention to quit. Supervisors' and colleagues' support was indirectly associated with the intention to quit via increasing job satisfaction and reducing the experience of mental health symptoms among paramedics only. Mental health symptoms were directly associated with the intention to quit and indirectly associated with the intention to quit via reducing job satisfaction among paramedics only.

The study findings provide evidence for resource allocation in human resource management. The findings suggest that interventions to increase job satisfaction may reduce the intention to quit for all ambulance personnel. Interventions to improve supervisors' and colleagues' support and to manage depression, anxiety and stress symptoms may help to reduce the intention to quit for paramedics only.

This is the first study to model and compare the direct and indirect associations of intention to quit between paramedics and non-paramedic staff in ambulance personnel.

The well-being of employees in distributed work has never been of more importance. This study aims to investigate the factors that empower or undermine the connectivity agency of teleworkers. Connectivity agency is an important form of autonomy for managing work–home boundaries, recuperation from work and psychological detachment. With this in mind it becomes vital to understand how connectivity agency is shaped by various contextual factors.

This qualitative study draws upon data collected from 27 teleworkers representing a variety of industries and roles. We employed a semi-structured interview protocol and analysed the data using Tracy’s (2013) iterative coding technique.

Factors that influence one’s likelihood or capacity to exercise connectivity agency exist at the individual, group or organisational level. Our data elucidate factors such as the provision of home and technological resources, the state of team norms and shared expectations and the level of organisational (dis)trust as having significant influence on whether a teleworker exercises connectivity agency, or whether attempts to do so fail altogether.

Whilst we have a comprehensive understanding of types of connectivity agency behaviours, it is unclear how one’s agency may be influenced by contextual factors. The originality and key contribution of our study is in enriching our understanding of connectivity agency to appreciate it as a dynamic phenomenon that is shaped by various contextual factors. This presents a variety of important insights for professionals leading, implementing or partaking in distributed work.

At the end of the case discussion, students should be able to trace the journey of launching a start-up by evaluating how opportunities and hurdles can be navigated throughout the international entrepreneurial process; assess the increasing trend towards internationalisation for start-ups and identify a range of factors contributing to the growth in global entrepreneurship; formulate an argument highlighting the role of the networking and partnerships when adopting a global strategy; propose how a firm could develop a unique mix of resources to obtain a sustained competitive advantage globally against other firms; and make an informed decision regarding various issues that entrepreneurs need to consider when going global and analyse how they can effectively deal with a crisis they may face.

Oryx Desert Salt is sourced from ancient, unpolluted, sustainable underground salt lakes in the pristine and remote uninhabitable Kalahari semi-desert of South Africa. Samantha Skyring is the founding CEO of Oryx Desert Salt. Her inspiration for the name was her 120-km, one-week walk through the Namib Desert in 2000, when she had several close encounters with the Oryx Gazelle, becoming the symbol of that Kalahari experience. Oryx products currently feature on the tables of between 1,500 and 2,500 local restaurants country-wide, and in the retail sector, Oryx salt is on the shelves of about 1,000 stores of retailers, plus in several health shops and deli’s countrywide. Regarding the business’s global footprint, Oryx Desert Salt currently exports to 23 countries and is also available on Amazon.com. Notwithstanding that Samantha Skyring has succeeded in making Oryx Desert Salt the well-known local household brand she had intended; she is contemplating greater international expansion and reach. She has envisioned Oryx salt to become a respected global household brand, in the same way Himalayan pink salt gained popularity worldwide as a gourmet salt. Given Samantha’s challenge of finding suitable speciality distributors in the different countries to help get her product in restaurants and retail, what would be the best approach to achieve her vision of becoming a global brand? To what extent could she capitalise and leverage various resources to further globalise Oryx’s business operations? How could she ensure that the extent and diversity of global reach provides Oryx Desert Salt with a sustained competitive advantage?

Master of Business Administration (MBA), Master of Management, Executive Education

Teaching notes are available for educators only.

CSS 3: Entrepreneurship.

Drawing from the human resource management (HRM) literature and framed with self-determination theory, this article seeks to investigate the impact of a hybrid system of HRM, characterized by the integration of practices from high-involvement work systems (HIWS) and high-compliance work systems (HCWS), on employee well-being in China.

We hypothesize there is a positive relationship between the hybrid system and employee well-being, mediated by the satisfaction of basic psychological needs as proposed by self-determination theory. To test these hypotheses, we conducted a cross-sectional survey involving 337 employees from both an agricultural company and a bank in China.

Our dataset provides support for the hypotheses, indicating that hybrid human resource (HR) systems positively relate to employee well-being, with a positive association with work engagement and a negative association with emotional exhaustion. Furthermore, our findings reveal that this relationship is mediated by the satisfaction of basic psychological needs.

This paper contributes to the HRM literature in three significant ways. First, it explores the hybrid HRM system, which integrates high-involvement work systems (HIWS) and high-compliance work systems (HCWS), enhancing the theorization of HRM in a more comprehensive manner. Second, it utilizes self-determination theory (SDT) to illuminate the underlying mechanisms connecting hybrid HRM to employee well-being – a topic that has received limited attention in prior research. Lastly, we operationalize employee well-being by examining both work engagement and emotional exhaustion, thereby offering a comprehensive understanding of its multidimensional nature.