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The purpose of this study is to determine the material extrusion (MEX) printability envelope of a new kind of low-viscosity powder-binder feedstocks using rheological properties.

Formulation of 13 feedstocks (variation of solid loading 60–67 Vol.% and thickening agent proportion 3–15 Vol.%) that were characterized and printed at different temperatures.

Three rheological models were successfully used to define the viscosity envelope, producing stable and defect-free printing. At a shear deformation rate experienced by the feedstock in the nozzle ranging from 100 to 300 s^–1, it was confirmed that metal injection molding (MIM) feedstocks exhibiting a low viscosity between 100 and 150 Pa s could be printed using an extrusion temperature as low as 85 °C.

MEX can be used in synergy with MIM to accelerate mold development for a new injected part or simply as a replacement for MIM when the cost of the mold becomes too high for very small production volumes.

Correlation between the rheological properties of this new generation of low-viscosity feedstocks and MEX printability has been demonstrated for the first time.

This study provides an up-to-date review of additive manufacturing (AM) technologies and guidance for selecting the most appropriate ones for specific applications, taking into account the main features, strengths, and limitations of the existing options.

A literature review on AM technologies was conducted to assess the current state-of-the-art. This was followed by a closer examination of different AM machines to gain a deeper insight into their main features and operational characteristics. The conclusions and data gathered were used to formulate a classification and decision-support framework.

The findings indicate the building blocks of the selection process for AM technologies. Furthermore, this work shows the suitability of the existing AM technologies for specific cases and points to opportunities for technological and decision-support improvements. Lastly, more standardization in AM would be beneficial for future research.

The proposed framework offers valuable support for decision-makers to select the most suitable AM technologies, as demonstrated through practical examples of its utilization. In addition, it can help researchers identify the limitations of AM by pinpointing applications where existing technologies fail to meet the requirements.

The study offers a novel classification and decision-support framework for selecting AM technologies, incorporating machine characteristics, process features, physical properties of printed parts, and costs as key features to evaluate the potential of AM. Additionally, it provides a deeper understanding of these features as well as the potential opportunities for AM and its impact on various industries.

This study aims to enhance merging of additive manufacturing (AM) techniques with powder injection molding (PIM). In this way, the prototypes could be 3D-printed and mass production implemented using PIM. Thus, the surface properties and mechanical performance of parts produced using powder/polymer binder feedstocks [material extrusion (MEX) and PIM] were investigated and compared with powder manufacturing based on direct metal laser sintering (DMLS).

PIM parts were manufactured from 17-4PH stainless steel PIM-quality powder and powder intended for powder bed fusion compounded with a recently developed environmentally benign binder. Rheological data obtained at the relevant temperatures were used to set up the process parameters of injection molding. The tensile and yield strengths as well as the strain at break were determined for PIM sintered parts and compared to those produced using MEX and DMLS. Surface properties were evaluated through a 3D scanner and analyzed with advanced statistical tools.

Advanced statistical analyses of the surface properties showed the proximity between the surfaces created via PIM and MEX. The tensile and yield strengths, as well as the strain at break, suggested that DMLS provides sintered samples with the highest strength and ductility; however, PIM parts made from environmentally benign feedstock may successfully compete with this manufacturing route.

This study addresses the issues connected to the merging of two environmentally efficient processing routes. The literature survey included has shown that there is so far no study comparing AM and PIM techniques systematically on the fixed part shape and dimensions using advanced statistical tools to derive the proximity of the investigated processing routes.

Personal Protective Equipment plays an inevitable part in the current scenario of pandemics in the world. A novel coronavirus, Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-Cov 2), began as an outbreak of pneumonia in Wuhan, China, in late December 2019, and quickly spread worldwide. It quickly escalated into an international public health crisis. This opened up the high demand for the innovation and research of new materials in the Personal Protective Equipment industry.

PubMed, Embase and Google Scholar were searched for relevant literature regarding personal protective equipment and the information was organized in a systematic way.

There are no adequate number of studies taken up in the field of use of textiles in medical applications especially with PPEs.

This structured review will generate a sense of the significance of using PPE for controlling pandemics and also awaken need for additional research and innovations in this area.

The authorities of the management should take timely intervention in choosing the right material for their PPE in their hospitals. Hence health care professionals teams have an inevitable role in preventing the adverse environmental impact due to the inadvertent disposal of PPEs.

There is a lack of systematic way of disposing contaminated single-use face masks in a safe, environmentally acceptable manner. The dumping of single-use PPE in domestic garbage has had an adverse effect on the environment. Mismanaged plastic waste endangers the health of ecosystems by polluting marine and terrestrial environments, posing a significant risk of ingestion or injury to animals and contaminating habitats.

This review article provides an in-depth review of the use of different materials in PPE and challenges regarding its long-term use and implications on the environment.

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

The purpose of this study is to explore the understanding and observance of the program “This School is a Zone of Peace” (SZOP) in schools where conflict and violence are not prevalent.

This paper followed a qualitative research tradition – narrative inquiry. Eight teachers and a school head participated in the study. Data were gathered through nonparticipant observation, photography and focus group discussion with photo elicitation.

The participants elucidated the declaration, “This School is a Zone of Peace,” as a message of assurance to the community that the school is a home for learners that is welcoming and violence free. Furthermore, learners in a school that is a zone of peace are honed holistically with the participation, cooperation and togetherness of the school community members. Teachers at the forefront viewed themselves as mentors, implementers and models. Teachers contended that peacebuilding practices in schools could be sustained through regular implementation, encouraging others to get involved and have commitment.

A handful of articles have illustrated the essence of the School as Zone of Peace program, which pointed out to create a culture of peace in schools; however, it leaned toward the negative conception of peace – the absence of conflict and violence. This study bared additional insights and fresh perspectives of the SZOP initiative observed in schools with different contexts and experiences that may be helpful to policymakers for the enhancement of the adapted program with the goal of peacebuilding to making schools highly functional.

This chapter uses narrative inquiry to tell the stories of two female neophyte educators experiencing the oppositional misalignment between their idealized perception of female teachers in American society and their personal realities by providing alternate images of women in education. American teachers, especially women, are perceived as a homogeneous group that lives to serve the children of others and inhabit a monochrome, two-dimensional, existence inside the educational landscape of schools (Clandinin & Connelly, 1996). However, the prevailing notions and outdated imagery of teachers is flawed in its lack of acknowledgment of the richly diverse and textured lived experiences of women both inside and outside of the educational field. Furthermore, female teachers face tremendous pressure to imitate these unrealistic ideals and expectations at the expense of the authentic self, which can lead to a myriad of internal dissonances, such as burnout, serving as an umbrella over PTSD, anxiety, compassion fatigue, decreased confidence, and lower job satisfaction. The researchers in this chapter come from nontraditional backgrounds to capture the negative effects of subtle, persistent, and unrealistic expectations of females that contribute to feelings of burnout at the onset of our teaching careers.

The study discusses the professionalization of academic leadership in Israel by analyzing and comparing two different training programs: the Hebrew University of Jerusalem’s (HUJI) program and the CHE-Rothschild program. The HUJI program began in 2016 to train the professoriate to take charge of leadership positions alongside a separate program for administrative staff, while the CHE-Rothschild program was launched in 2019 to train academic leaders, both professors and administrators from universities and colleges nationwide. The analysis reveals two “ideal types” of collegiality: While Model A (exemplified by the HUJI program) bifurcates between the professoriate and administrative staff, Model B (exemplified by the CHE-Rothschild program) binds administrative and academic staff members through course composition, pedagogy, and content. The study suggests a pattern of redefinition of collegiality in academia: we find that while academic hierarchies are maintained (between academic faculty and administrative staff and between universities and colleges), collegiality in academia is being redefined as extending beyond the boundaries of the professoriate and emphasizing a partnership approach to collegial ties.

The purpose of this paper is to examine the effect of changing some riveting parameters on the riveting quality of a riveted aircraft structure. In this study, riveting was performed by applying friction under pressure.

During this friction riveting process, a feed of 3 mm/min was applied in the axial direction. Rotation speed values of 2,000, 2,200 and 2,400 rpm were selected. A 3-axis die milling machine was used to achieve the required positioning, pressing force and friction effect. 1.27 mm-thick Al 7075-T6 sheets and 2117-T3 forged rivets were used. The feed rate was applied at 1 mm/min in both tensile shear and cross-tensile tests.

The feasibility of friction riveting in 2117-T3 rivets was examined, it was shown that it could be done, and the most suitable rotation value for this process was determined.

Clamping force is one of the most important parameters for riveting quality. This study will contribute to a better understanding of the friction-forging riveting process along with the effects of riveting parameters. At the same time, it will lead to more research and expand the application of friction forging riveting to more structural connections.

The purpose of this study is to investigate the gendered ideas and ideals attached to an imagined ideal Entrepreneur in a post-industrial rural community in Sweden. While research has not yet clearly explained how the ideal entrepreneur is constructed, the result, i.e. the gendered representations of entrepreneurs, is well-researched. Previous results indicate a prevalent portrayal of entrepreneurship as a predominantly masculine construct characterised by qualities such as self-made success, confidence and assertiveness.

Ethnographic fieldwork was conducted in a community that is attempting to re-brand itself through garden tourism. Through inductive reasoning, this study analyses the gendered ideas and ideals regarding the community’s imagined ideal Entrepreneur who is to help the community solve its problems.

This study finds that the community forges the Entrepreneur into an imagined masculine ideal as holy, a saviour and a god and is replacing its historical masculine ironmaster with a masculine Entrepreneur. This study develops forging as a metaphor for the construction of the masculine ideal Entrepreneur, giving the community, rather than the entrepreneur himself, a voice as constructors. From social constructionism, this study emphasises how gendered ideas and ideals are shaped not only by the individual realities but more so in the reciprocal process by the realities of others.

The metaphor of forging adds an innovative theoretical dimension to the feminist constructionist approach and suggests focusing on how the “maleness” of entrepreneurship is produced and reproduced in the local. Previously, light has been shed on how male entrepreneurs perform their identities collectively; the focus of this study is on the social construction of this envisioned Entrepreneur within a rural community. The development of forging thus contributes as a way of analysing entrepreneurship in place. The choice of an ethnographic study allowed the authors to be a part of the real-life world of community members, providing rich data to explore entrepreneurship and gender.