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This paper aims to develop a Mini-Tribometer for in-situ observation of subsurface.

To observe the change of the microstructure during wear in real time, an in-situ observation mini-tribometer was developed according to the requirements of the basic frictional experiments and carried out the verification experiments.

The subsurface images and the tribological data obtained from the mini-tribometer clearly show that the graphite in the matrix moves to the surface and takes part in lubrication mainly in the form of extrusion and peeling off, and the migration of graphite in the copper-based composite to the frictional interface to act as lubricant and to result in the decrease of the friction coefficient. The experimental results of the developed tribometer are accurate, which can provide important references for further research on the wear mechanism of materials.

The developed in-situ observation mini-tribometer can be used to observe the dynamic wear mechanism of the frictional pairs, which is very important for optimization of material design and tribological performances.

Powder lubrication is widely used in industrial production, but most of the research that analyze the wear process and speculate on the wear mechanism of the tested specimens lacks reliability, and it is difficult to reveal the essence of the friction and wear process. The purpose of this paper is using the optical in situ observation method to observe the condition of the powder lubrication layer in real time and dynamically, and directly obtain the morphology change of the specimen during the whole wear process, which is helpful to the establishment of new tribological basic theories such as friction and wear mechanism and lubrication theory.

Mechanical model of powder lubrication is established considering asperity and powder layer, and the influence of adhesion effect on load and friction force is analyzed. The finite difference method is used to solve the above physical model, and the influence of the adhesion effect on load and friction force is analyzed. The total load and friction of the friction pair are composed of two parts: fluid and asperity. Based on the optical in situ observation method to build a test platform. The interface of the adhesion stage was observed by SEM.

When the film thickness ratio is less than 1, the local damage and diffusion of the powder layer are basically completed and the adhesion stage is entered. At this time, the asperity is not fully loaded, the powder layer is loaded by 50%, the asperity is less loaded, the deformation is small and the possibility of plastic flow is reduced. However, in the adhesion stage, the friction force is basically generated between asperity, and the friction force ratio of the asperity is 80%. Heavy load and surface roughness of the specimen are the necessary conditions for the powder adhesion period.

In this paper, the failure process of the powder layer at the friction interface with different roughness and load is studied based on the optical in situ observation method. Second, the contact surface with the micro-convex body and powder layer is simulated, and the influence of adhesion effect on the mechanical properties of the real contact surface in the process of powder lubrication is analyzed, thus providing theoretical guidance for mechanical processing, workpiece operation and lubrication design.

Mechanical model considering asperities and powder layer powder lubrication was established to analyze the influence of the adhesion effect on load and friction. Based on the optical in situ observation method to build a test platform. The tests found that the failure process of the powder lubricating layer includes five stages: powder complete stage, local failure stage, local failure diffusion stage, powder adhesion stage and complete failure stage.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0322/

This paper aims to investigate the corrosion evolution process of AZ91 magnesium alloy in 3.5 wt.% NaCl solution under different stresses by using in situ methods, thereby evaluate the influence of stress on the corrosion sensitivity of AZ91 magnesium alloy, and discuss the potential mechanism.

A four-point bending method was used to apply different loads to the magnesium alloy samples, a charge coupled device camera and electrochemical impedance spectroscopy test being used for in situ study. Scanning electron microscopy and X-ray diffraction (XRD) analysis were performed for corrosion product and morphology characteristics.

The observation results show that the corrosion of AZ91 magnesium alloy becomes more and more serious with the increase in the stress and generated many corrosion products. Originally, corrosion products prevented alloy matrix from contacting the corrosive medium. However, the increase in the stress facilitated the emergence of the corrosion holes in the corrosion products, which provided the microscopic channels for corrosive solution to attack the Mg alloy matrix, and accelerated the corrosion of the magnesium alloy, resulting in a lot of corrosion pits on the magnesium alloy surface under the corrosion product layer.

The evolution information of corrosion process is crucial to explore the mechanism of corrosion. Currently, most researches about corrosion of magnesium alloy used traditional testing techniques to obtain corrosion information, lacking the direct tracking and monitoring of the corrosion evolution process. Hence, this paper focuses on in situ corrosion study of AZ91 magnesium alloy. The technology with spatial resolution capability observed the changes in magnesium alloy surface at different times in the corrosion process in situ. Meanwhile, the in situ electrochemical technology was used to monitor the changes in micro-electrochemical signals during the corrosion process of magnesium alloy under different stresses.

This study aims to discover how leadership emerges in a hospital’s trauma team in a simulated trauma care situation. Instead of investigating leadership from a leader-centric perspective, or using a metrics-based approach to reach generalizable results, the study aims to draw from post-heroic theories by applying leadership-as-practice and sociomaterial perspectives that emphasize the cultural-historical context and emergent nature of leadership.

The study was conducted in a Finnish central hospital through ethnographic observations of 14 in situ trauma simulation trainings over a period of 13 months. The data consist of vignettes developed and written from field notes. The analysis was informed by the cultural-historical activity theory.

Leadership in a trauma team during an in situ simulation training emerges from a complex system of agencies taking place simultaneously. Contextual elements contributed to the goal. Clarity of roles and task division, strong execution of leadership at critical points, active communication and maintenance of disciplined communication helped to overcome difficulties. The team developed coordination of the process in conjunction with the care.

The study considers trauma leadership to be a practical phenomenon emerging from the trauma team’s sociomaterial context. The results can be used to develop non-technical skills training within the field of simulation-based medical training.

The purpose of this paper is to review the application of digital holography in studies of the corrosion of metallic materials.

Digital holography is used for in situ observation of the dynamic processes at the electrode | electrolyte interface and on the electrode surface during the corrosion dissolution of metallic materials.

Digital holography is an effect method to in situ observe the corrosion processes, and it can provide a direct experimental foundation for studying the corrosion mechanism.

Even though there are several challenges, digital holography will play a significant role in studying corrosion processes.

The purpose of this paper is to explore the dynamics of marketing practice and theory in arguing that much of the dislocation between strategy and practice is due to the inheritance and internalisation of often impractical but persistently dominant, tacit Cartesian assumptions.

This paper uses case methodology to examine the marketing theory into practice/marketing practice into theory conundrum and explores: their separation (marketing theory and marketing practice); their flows (context to text to context: theory into practice/practice into theory); their symbiosis (the praxis of marketing); and the dynamic and static (in situ/in aspic) nature of their duality. This work is an exploratory empirical study undertaken in what is a very under-researched area.

In this paper, marketing theory and marketing practice are recognised as occupying different epistemes. The lifeworld of marketing theorising appears as characterised by a relatively homogenous and mostly cognitive world dominated by rationality and empirical rigour. By contrast, the embodied practitioner inhabits a more highly segmented, fragmented, heterogeneous and frequently improvised landscape.

The authors propose that the all-consuming clamour for reliance and relevance of theory to practice dictates that the form, function and philosophy of marketing must be co-created in the practical pragmatism of praxis. Praxis is practice informed by theory and theory informed by practice, a cyclical process of experiential, contextual learning.

The paper appears to be the first to bring together Cartesian thought and the practice-theory divide in B2B marketing theory.

The purpose of this paper is to study the phenomenon of organizational change failure through an emic approach. Grounded in empirical examples, the paper unfolds why the phenomenon seems to be missing from the literature of the becoming view (e.g. Tsoukas and Chia, 2002).

Inspired by the methodological strategy of “studying through,” organizational changes are followed through space and time within the setting of a Nordic bank, from where the empirical data have been collected via longitudinal study. The empirical data are generated through a combination of methods: shadowing, interviews, in situ observations and desk research in order to capture the ever-changing phenomenon of organizational change.

The paper finds that organizational changes drift away, either by slipping into the everyday practices of the organization, or by drifting away in time when history is reinterpreted. The paper concludes that organizational change failures suffer the same fate as organizational changes more generally and drift away in space and time.

The paper contributes to the becoming view by illustrating how methodologically an ever-changing phenomenon such as organizational change can be studied. Further, it contributes to the field of organizational change failure by unpacking the fate of organizational change failure when change is natural and slippery in nature. The paper includes reflections on what the consequences might be for praxis.

The purpose of this paper is to report on a study of the movement of the powder bed material during selective laser sintering (SLS) of bisphenol‐A polycarbonate (PC) powder and its effect on the morphology of the sintered specimen.

Two sintering experiments, i.e. single‐spot laser sintering and raster‐scan laser sintering, were carried out and the material movement mechanisms were investigated in situ and subsequently by scanning electron microscopy.

During the raster‐scan laser sintering process, the movement of the powder was found to be primarily perpendicular to the scanning direction. When sintering at a high laser power, it significantly affected the surface morphology of the sintered specimens and parallel surface bands occurred along the scanning direction.

Experiments were carried out on a modified laser engraving machine rather than a commercial SLS machine.

A schematic model of the material movement mechanism for each of the sintering strategies is presented.

The results further the understanding of the sintering behaviour of the powder bed.

This paper reports on a method for in‐situ observation of the morphology and stability of electrochemically generated metal layers. This information is obtained by comparing topographical and kinetic data. The method is based on coulometric, microgravimetric and optical measurement performed in situ on vertically growing electrodes. Measurements are obtained simultaneously from the same surface area.