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The purpose of this paper is to examine the connections between vision statements, leadership and human resource management (HRM) to clarify what contribution HRM has to make in translating an organizational goal into a vision statement.

The importance of vision statements is explained. Empirical data are used to illustrate the failure of many companies to exploit the potential of a vision statement. Finally, the role of HRM in formulating a vision statement is discussed.

“Vision statement” is another term for primary organizational goal. Setting this primary goal is an indispensable task of leadership. If the vision statement is missing, HRM should remedy the situation.

The added value of this paper lies in explaining why vision statements are relevant for both leadership and HRM and the functions and leading role of HRM in actualizing the vision statement.

The purpose of this paper is to differentiate the ambidextrous leadership concept into direct and indirect types to provide an alternative when the requirements of direct ambidextrous leadership cannot be met.

Desk research is used in this paper to relate the ambidextrous leadership concept to the roles of leader and manager to more comprehensively determine the requirements for being a direct/indirect ambidextrously leading executive than is possible by referring only to opening and closing leadership or exploration and exploitation.

Special requirements in the context of ambidextrous leadership can be transferred from the top executive/chief executive officer to third parties, for example, some control tasks in the area of exploitation can be distributed among the top management team, enabling the top executive to focus on tasks such as developing an organisation-wide vision and its strategic implementation. Indirect ambidextrous leadership exists if the top executive distributes exploitation tasks to third parties. Direct ambidextrous leadership exists if the top executive assumes leadership in both the exploration and exploitation areas. This means that the demands on the top executive are different in direct ambidextrous leadership and in indirect ambidextrous leadership.

The literature has not yet focused on the differentiation between direct and indirect ambidextrous leadership. This paper contributes towards closing this gap. The potential for indirect ambidextrous leadership can be essential for a company’s success because in addition to direct ambidextrous leadership, it represents the possibility of creating a sustainable organisation in a changing market.

The purpose of this paper is to introduce the subjective perspective via the transition approach to organizational career planning so that employees’ individual transition phases can be evaluated, planned and guided.

A theoretical–conceptual analysis is conducted in this paper.

The individual perspective can be included in career planning via the transition approach. By dividing the transition into individual phases, the different requirements of employees over the course of time can be analysed individually and corresponding measures (for example coaching) can be derived.

The added value of this paper is that organizational career planning can individually analyse employees’ transitions, using a transition approach, increasing the likelihood of a successful transition.

This work aims to analyse the flexibility-stability continuum and explore the question of where the best equilibrium lies on this continuum and to what extent it can be realized.

After analysing the concepts of flexibility and stability, along with their trade-off relationship, from a theoretical standpoint, the optimum in the flexibility-stability continuum is determined by means of a triangulation of theories. The subsequent operation to determine best possible practice is also accomplished via a theoretical analysis.

Organizational flexibility and stability are two poles of a continuum that are interdependent. The optimum in a flexibility-stability continuum lies, according to Gossen's first law, where marginal utility is zero. Determination of the optimum requires a great deal of information, however, which is difficult to collate and process because of its complexity. As an alternative to the “optimum”, “best possible practice” is introduced. This provides an alternative to the less satisfactory method of “best practice according to benchmarking.”

The value of this work lies in finding an optimum in the flexibility-stability continuum. As the (theoretical) optimum is difficult to determine and realize due to inherent complexities, “best possible practice” is presented as an alternative. This takes into account the idea of optimization meaning no improvement is possible if the goal is achieved. “Best possible practice” defines an implementable, best possible state that can be used for organizational goal formulation. To achieve the best possible equilibrium in the flexibility-stability continuum, the respective advantages of stability and flexibility should be ideally exploited to lead to competitive advantage.

This paper determines and analyses criteria for top executives to use in appraisal systems to promote ambidextrous leadership, enhancing the organization's ability to identify persons who can lead ambidextrously or determining the development potential of existing top executives.

Using a theoretical-conceptual, triangulated approach, the investigation in this paper examines the requirements for top executives to lead ambidextrously. In a subsequent review and frequency analysis, the specific attributes/behaviours a top executive should possess are examined. Analysis of the application of these appraisal criteria is theoretical.

The criteria listed in this paper (e.g. ambition, courage, vision) can be used to foster ambidextrous leadership when hiring or evaluating performance. These and/or the criteria already existing in an organization should be classified in one of the two categories presented (1. one-dimensional criteria: differentiation between exploration/exploitation is not necessary; 2. multidimensional criteria: differentiation between exploration and exploitation, opening and closing leadership, and first- and second-order changes is necessary) to differentiate the criteria and thereby illuminate their application in the areas of exploration and exploitation. Thus, a corresponding assessment of applicants and/or job holders for ambidextrous leadership is possible.

This theoretical analysis contributes to the literature on top executives' recruitment, performance management, career and succession planning, focusing on ambidextrous leadership and organizational development by elucidating a differentiated concept for appraisal criteria so that the right person can be appointed to the top executive position or assigned to the necessary personnel development programme. Thus identified, a top executive may be positioned to maintain, improve or install ambidextrous leadership and practice in an organization.

The purpose of this paper is to analyse the signal dependency of the camera-based coaxial monitoring system QMMeltpool 3D (Concept Laser GmbH, Lichtenfels, Germany) for laser powder bed fusion (LPBF) under the variation of process parameters, position, direction and layer thickness to determine the capability of the system. Because such and similar monitoring systems are designed and presented for quality assurance in series production, it is important to present the dominant signal influences and limitations.

Hardware of the commercially available coaxial monitoring QMMeltpool 3D is used to investigate the thermal emission of the interaction zone during LPBF. The raw images of the camera are analysed by means of image processing to bypass the software of QMMeltpool 3D and to gain a high level of signal understanding. Laser power, scan speed, laser spot diameter and powder layer thickness were varied for single-melt tracks to determine the influence of a parameter variation on the measured sensory signals. The effects of the scan direction and position were also analysed in detail. The influence of surface roughness on the detected sensory signals was simulated by a machined substrate plate.

Parameter variations are confirmed to be detectable. Because of strong directional and positional dependencies of the melt-pool monitoring signal a calibration algorithm is necessary. A decreasing signal is detected for increasing layer thickness. Surface roughness is identified as a dominating factor with major influence on the melt-pool monitoring signal exceeding other process flaws.

This work was performed with the hardware of a commercially available QMMeltpool 3D system of an LPBF machine M2 of the company Concept Laser GmbH. The results are relevant for all melt-pool monitoring research activities connected to LPBF, as well as for end users and serial production.

Surface roughness has not yet been revealed as being one of the most important origins for signal deviations in coaxial melt-pool monitoring. To the best of the authors’ knowledge, the direct comparison of influences because of parameters and environment has not been published to this extent. The detection, evaluation and remelting of surface roughness constitute a plausible workflow for closed-loop control in LPBF.

The purpose this paper is to develop an additive manufacturing (AM) technique for high‐strength oxide ceramics. The process development aims at directly manufacturing fully dense ceramic freeform‐components with good mechanical properties.

The selective laser melting of the ceramic materials zirconia and alumina has been investigated experimentally. The approach followed up is to completely melt ZrO₂/Al₂O₃ powder mixtures by a focused laser beam. In order to reduce thermally induced stresses, the ceramic is preheated to a temperature of at least 1,600°C during the build up process.

It is possible to manufacture ceramic objects with almost 100 percent density, without any sintering processes or any post‐processing. Crack‐free specimens have been manufactured that have a flexural strength of more than 500 MPa. Manufactured objects have a fine‐grained two‐phase microstructure consisting of tetragonal zirconia and alpha‐alumina.

Future research may focus on improving the surface quality of manufactured components, solving issues related to the cold powder deposition on the preheated ceramic, further increasing the mechanical strength and transferring the technology from laboratory scale to industrial application.

Potential applications of this technique include manufacturing individual all‐ceramic dental restorations, ceramic prototypes and complex‐shaped ceramic components that cannot be made by any other manufacturing technique.

This new manufacturing technique based on melting and solidification of high‐performance ceramic material has some significant advantages compared to laser sintering techniques or other manufacturing techniques relying on solid‐state sintering processes.

The purpose of this paper is to compare different powder metallurgy (PM) processes to produce ceramic parts through additive manufacturing (AM). This creates the potential to rapidly shape ceramic parts with an almost unlimited shape freedom. In this paper, alumina (Al₂O₃) parts are produced, as Al₂O₃ is currently the most commonly used ceramic material for technical applications.

Variants of the following PM route, with indirect selective laser sintering (indirect SLS) as the AM shaping step, are explored to produce ceramic parts: powder synthesis, indirect SLS, binder removal and furnace sintering and alternative densification steps.

Freeform-shaped Al₂O₃ parts with densities up to approximately 90 per cent are obtained.

The resulting Al₂O₃ parts contain inter-agglomerate pores. To produce higher-quality ceramic parts through indirect SLS, these pores should be avoided or eliminated.

The research is innovative in many ways. First, composite powders are produced using different powder production methods, such as temperature-induced phase separation and dispersion polymerization. Second, four different binder materials are investigated: polyamide (nylon-12), polystyrene, polypropylene and a carnauba wax – low-density polyethylene combination. Further, to produce ceramic parts with increased density, the following densification techniques are investigated as additional steps of the PM process: laser remelting, isostatic pressing and infiltration.

Selective laser melting (SLM) is a powder metallurgical (PM) additive manufacturing process whereby a three‐dimensional part is built in a layer‐wise manner. During the process, a high intensity laser beam selectively scans a powder bed according to the computer‐aided design data of the part to be produced and the powder metal particles are completely molten. The process is capable of producing near full density (∼98‐99 per cent relative density) and functional metallic parts with a high geometrical freedom. However, insufficient surface quality of produced parts is one of the important limitations of the process. The purpose of this study is to apply laser re‐melting using a continuous wave laser during SLM production of 316L stainless steel and Ti6Al4V parts to overcome this limitation.

After each layer is fully molten, the same slice data are used to re‐expose the layer for laser re‐melting. In this manner, laser re‐melting does not only improve the surface quality on the top surfaces, but also has the potential to change the microstructure and to improve the obtained density. The influence of laser re‐melting on the surface quality, density and microstructure is studied varying the operating parameters for re‐melting such as scan speed, laser power and scan spacing.

It is concluded that laser re‐melting is a promising method to enhance the density and surface quality of SLM parts at a cost of longer production times. Laser re‐melting improves the density to almost 100 per cent whereas 90 per cent enhancement is achieved in the surface quality of SLM parts after laser re‐melting. The microhardness is improved in the laser re‐molten zone if sufficiently high‐energy densities are provided, probably due to a fine‐cell size encountered in the microstructure.

There has been extensive research in the field of laser surface modification techniques, e.g. laser polishing, laser hardening and laser surface melting, applied to bulk materials produced by conventional manufacturing processes. However, those studies only relate to laser enhancement of surface or sub‐surface properties of parts produced using bulk material. They do not aim at enhancement of core material properties, nor surface enhancement of (rough) surfaces produced in a PM way by SLM. This study is carried out to cover the gap and analyze the advantages of laser re‐melting in the field of additive manufacturing.

The purpose of this paper is to provide macromechanical insight into the fatigue behaviour of laser sintered parts and to understand the influence of the laser sintered surface structure on this behaviour.

A background on the technological maturity of manufacturing processes and the demand for structural and aesthetic properties of laser sintered plastic products is given. As the contribution of surface structure on part quality was the focus, laser sintered specimens with and without surface finishes, as well as injection moulded specimens were used. The latter simply served as a comparison and was not intended to qualify injection moulding. The study comprises the determination of short‐term tensile properties, the load increase method for investigating fracture and deformation behaviours, and fatigue crack propagation analysis.

According to the test results, the contribution of laser sintered surface structures to relevant mechanical properties can be neglected. Under dynamic loading conditions, laser sintered specimens achieved a longer lifetime but showed less deformation capabilities in contrast to injection moulded specimens. In general, laser sintered specimens presented considerable resistance to crack initiation and propagation.

Because of the long‐term approach of the research, the number of tests conducted per lot was limited. Thus, the effects of different process settings and the reproducibility could not be fully analysed.

The studied fatigue behaviour of laser sintered specimens has implications for the functional testing of parts or components, for the product and process design as well as for the general compatibility of laser sintering as a manufacturing technology of end‐customer products.

The value of this paper lies in the better understanding of deformation and fracture behaviours of laser sintered polymers.