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The purpose of this paper is to introduce a numerical calculation method to study the uniformity of the magnetic field in a cold crucible used for directional solidification (DS) and provide information for designing a cold crucible that can induce a uniform magnetic field.

To obtain the characteristics of the magnetic field in a cold crucible and its influence on the directional solidification processing, based on experimental verification, 3‐D finite element (FE) models with different crucible configuration‐elements and power parameters were established to study the uniformity of the magnetic field in a cold crucible. In addition, different TiAl ingots were directionally solidified with different cold crucibles, and the solid/liquid (S/L) interfaced were examined to investigate the effect of the magnetic field on the macrostructure of those ingots.

The uniformity of the magnetic field in a given domain can be quantitatively analyzed by statistical methods. Numerical calculation results showed that the uniformity of the magnetic field can be improved by optimizing the crucible configuration and adopting lower frequency. Better uniformity of the magnetic field in a cold crucible is beneficial to directional solidification.

The calculation of the uniformity of the magnetic field is proposed as a method for quantitative study of the distribution characteristics of the magnetic field in a cold crucible. The relationship between the S/L interfaces of TiAl ingots and the uniformity of the magnetic field is initially characterised; additionally, techniques for improving the uniformity of the magnetic field in a cold crucible are suggested.

Despite the widespread attribution that stressful crucible experiences result in important individual developmental change within leaders, a deeper exploration of the mechanisms of that change is warranted. Likewise, literature linking the crucible and individual change to social and organizational considerations, including how organizations can plan for and sponsor institutionalized crucibles, is sparse. Thus, the intent of this chapter is to begin to synthesize the crucible, cognitive development, and stress literatures to show important linkages, risks, and outcomes, then provide a basic blueprint of planning considerations for organizations that desire to establish their own crucible events that target leader development.

Comprehensive knowledge of the complicated physical behavior of the induction furnace with cold crucible (IFCC) is required to utilize the advantages of this melting aggregate in melting and casting chemically high‐reactive materials, like titanium‐aluminides (TiAl). Practical experiences show that the overheating temperature of the melt is decisive for the quality of the cast products. Therefore, a systematic analysis of the electromagnetic and in particular, the hydrodynamic and thermal behavior of the IFCC is carried out. The examinations of the influence of the construction elements as well as the process parameters on the temperature field and finally the overheating temperature in the IFCC are performed using specifically developed numerical models. The evaluation of the numerical results is done by experimental investigations, where aluminum serves as a model melt for the experimental determination of the thermal and hydrodynamic field of the melt. The analysis of the influence of construction‐elements on the overheating temperature is focused on the design of the crucible wall and the crucible bottom, on the height‐diameter ratio of the crucible and on the axial inductor position. The inductor current, the operation frequency and the crucible filling level are found to be very important for reaching a high overheating temperature.

A finite difference simulation for the bulk single crystal growth of indium phosphide by the liquid encapsulated vertical gradient freezing (LE‐VGF) method with a flat bottom crucible is presented. In order to treat a curvature interface, the boundary fixing method is applied. The transient behavior of the flow and temperature fields, the melt/crystal interface shape and the growth rate during growth are studied numerically. The crystal growth rate is not constant although the temperature lowering rate is constant. The effect of crucible thickness, thermal conductivity of the crucible and temperature of the growth furnace wall on the crystal growth behavior are discussed.

The purpose of this study is to examine the role of trigger events and leadership crucibles in the lives of authentic leaders. The study was based on two theories: authentic leadership theory and born versus made theory.

Participants were included in the study if they scored between 64 and 80 on the Authentic Leadership Questionnaire (ALQ). The qualified leaders were then asked to participate in a qualitative interview utilizing an interview guide born out of the relevant literature. The interview followed the guidelines of the Critical Incident Technique (CIT).

The data indicated that trigger events and leadership crucibles play a significant role in authentic leadership development.

Practitioners should emphasize the prominent themes of self-awareness, relational transparency, balanced processing and moral perspective and the connection with other themes that emerged from the current study when developing or training leaders. Furthermore, practitioners concerned with creating an authentic leadership culture may consider the findings of the current study to develop and employ hiring and promotion strategies that increase the probabilities of hiring and promoting leaders that exhibit authentic leadership behaviors.

The findings of the research indicate that trigger events and crucibles both affect authentic leadership development. The research findings confirm characteristics associated with authentic leadership theory were predominant in the participants. However, one theme that prevailed was that of spirituality, which may or may not be considered to be part of an authentic leader's moral perspective

A small size cold crucible offers possibilities for melting various electrically conducting materials with a minimal wall contact. Such small samples can be used for express contamination analysis, preparing limited amounts of reactive alloys or experimental material analyses. Aims to present a model to follow the melting process.

The presents a numerical model in which different types of axisymmetric coil configurations are analysed.

The presented numerical model permits dynamically to follow the melting process, the high‐frequency magnetic field distribution change, the free surface and the melting front evolution, and the associated turbulent fluid dynamics. The partially solidified skin on the contact to the cold crucible walls and bottom is dynamically predicted. The segmented crucible shape is either cylindrical, hemispherical or arbitrary shaped.

The model presented within the paper permits the analysis of melting times, melt shapes, electrical efficiency and particle tracks.

The purpose of this article is to explore different types of crucible experiences – transformative events that happen both on and off the job and that are the raw material from which outstanding leaders derive their core qualities.

Primarily through interviews with leaders in a wide range of organizations, the author analyzed nearly 200 crucible experiences and identified three varieties: “New Territory” (encounters with the unknown); “Reversal” (loss, impairment, or defeat); and “Suspension” (an extended period of contemplation).

Each type of crucible conveys different lessons for aspiring or established leaders. While the lessons vary, common themes emerge: the importance of relying on others; the interdependence of people within organizations; the need to continually ask questions, not just give answers; the importance of having a mission and recognizing that you are not bulletproof.

The article takes the idea of learning from experience and gives it a unique twist by focusing on life's most difficult experiences. Readers will appreciate the need to get out of the classroom and to mine the value of their own experiences.

Aims to present recent activities in numerical modeling of cold crucible melting process.

3D numerical analysis was used for electromagnetic problem and 3D large eddy simulation (LES) method was applied for fluid flow modeling.

The comparative modeling shows, that higher H/D ratio of the melt is more efficient when total power consumption is considered, but this advantage is held back by higher heat losses through the crucible walls. Also, calculations reveal that lower frequencies, which are energetically less effective, provide better mixing of the melt.

3D electromagnetic model, which allows to take into account non‐symmetrical distribution of Joule heat sources, together with transient LES fluid flow simulation gives the opportunity of accurate prediction of temperature distribution in the melt.

This study aims to explore the individual lived crucible experiences of women leaders in higher education (HE) and business as the catalyst to investigate organisational inequality regimes that prevent women leaders from fully participating, contributing and flourishing at work. Drawing upon Bolman and Deal’s four-frame theoretical organisational model, this study analyses women’s lived crucible leadership experiences to better understand the organising processes and practices that render intersectionality invisible that reinforce and perpetuate inequality regimes.

A collaborative autoethnographic research method was selected for data collection. The research team members each selected one significant crucible moment from their professional career and used the Gibb’s six-part reflective cycle to document their narrative and reflect on their leadership experience. A reflexive thematic analysis was used based on Braun and Clarke’s six phases.

The study features the importance of creating a climate in organisations that acknowledges the need for greater equity, diversity and inclusion (EDI) to support women leaders. Four global themes emerged from the analysis of the leadership narratives: organisation, power dynamics, emotional distress and perseverance and intersectionality. These themes illuminate a greater understanding of organisational life for women and confirm the presence of inequality regimes of gender and race.

This is the first study to explore the impact of women leaders’ crucible experiences through the lens of the Bolman and Deal’s model that highlights the need to consider an EDI lens as the fifth frame.