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The consolidation process and morphology evolution in ceramics-based additive manufacturing (AM) are still not well-understood. As a way to better understand the ceramic selective laser sintering (SLS), a dynamic three-dimensional computational model was developed to forecast thermal behavior of hydroxyapatite (HA) bioceramic.

AM has revolutionized automotive, biomedical and aerospace industries, among many others. AM provides design and geometric freedom, rapid product customization and manufacturing flexibility through its layer-by-layer technique. However, a very limited number of materials are printable because of rapid melting and solidification hysteresis. Melting-solidification dynamics in powder bed fusion are usually correlated with welding, often ignoring the intrinsic properties of the laser irradiation; unsurprisingly, the printable materials are mostly the well-known weldable materials.

The consolidation mechanism of HA was identified during its processing in a ceramic SLS device, then the effect of the laser energy density was studied to see how it affects the processing window. Premature sintering and sintering regimes were revealed and elaborated in detail. The full consolidation beyond sintering was also revealed along with its interaction to baseplate.

These findings provide important insight into the consolidation mechanism of HA ceramics, which will be the cornerstone for extending the range of materials in laser powder bed fusion of ceramics.

The ceramic tile chain can generate several environmental impacts, from raw material extraction to the production process, commercialization, consumption, maintenance and disposal. One of the open issues remaining in the literature on socially responsible supply chains, also known as responsible supply chains, is understanding how corporate social responsibility (CSR) practices are being implemented in ceramic tile companies in Brazil.

The method adopted is a multiple-case study. The authors conducted face-to-face interviews with six ceramic producers and a trade association. The authors also conducted eight interviews with specialists in the ceramic sector. They are two university professors, two class association representatives, one professional from a technological institute, two representatives of the inspection body and one supplier.

Companies perform on a compliance basis, manifesting a less proactive position when the subject is CSR. In addition, the CSR practices established by the companies are preferably aimed at reducing costs and risks and increasing reputation. Practices in terms of eco-design are linked to lowering costs and growing reputation, as seen from the reduction in the use of inputs and improvements in packaging to minimize costs. These practices improve the company’s reputation from the consumers' perspective. Environmental aspects are dominant due to the legislation.

This paper contributes theoretically since it identifies, from the companies' perspective, the CSR practices related to risk, cost reduction and reputation increase. There are also opportunities to be explored for facilitating their efforts towards a sustainable business model, especially considering the social dimension. From a managerial perspective, this paper provides some input for implementing CSR actions, mainly regarding their implications for society and local communities.

La cadena de revestimiento cerámico puede generar diversos impactos ambientales, desde la extracción de la materia prima hasta el proceso de producción, comercialización, consumo, mantenimiento y disposición. Una de las cuestiones abiertas que quedan en la literatura sobre cadenas de suministro socialmente responsables, también conocidas como cadenas de suministro responsables, es comprender cómo se están implementando prácticas de responsabilidad social empresarial en las empresas de revestimientos cerámicos en Brasil.

El método utilizado en el estudio es un estudio de casos múltiples. Realizamos entrevistas cara a cara con 6 productores de cerámica y una asociación comercial. También recibimos información de 8 especialistas representantes de organizaciones relacionadas con el sector cerámico; 2 profesores universitarios; 2 representantes de asociaciones de clase; 1 profesional de instituto tecnológico; 2 representantes del organismo de control; y 1 proveedor de esmaltes.

Las empresas actúan sobre la base del cumplimiento, manifestando una posición menos proactiva cuando el tema es la RSE. Además, las prácticas de RSC establecidas por las empresas están preferentemente encaminadas a la reducción de costes y riesgos y al aumento de la reputación. Las prácticas en materia de ecodiseño están esencialmente ligadas a la reducción de costos y al aumento de la reputación, a partir de la reducción en el uso de insumos y mejoras en los empaques para minimizar costos. Estas prácticas mejoran la reputación de la empresa desde la perspectiva de los consumidores. Los aspectos ambientales son dominantes debido a la legislación.

Este trabajo aporta teóricamente ya que identifica, desde la perspectiva de las empresas, las prácticas de RSE relacionadas con el riesgo, la reducción de costos y el aumento de la reputación. También hay oportunidades por explorar para facilitar sus esfuerzos hacia un modelo de negocio sostenible, especialmente teniendo en cuenta la dimensión social. Desde la perspectiva gerencial, este documento proporciona algunos insumos para la toma de decisiones sobre la implementación de acciones de RSE, principalmente en lo que respecta a las implicaciones para la sociedad y las comunidades locales.

Unconventional machining processes, particularly ultrasonic vibration cutting (UVC), can overcome such technical bottlenecks. However, the precise mechanism through which UVC affects the in-service functional performance of advanced aerospace materials remains obscure. This limits their industrial application and requires a deeper understanding.

The surface integrity and in-service functional performance of advanced aerospace materials are important guarantees for safety and stability in the aerospace industry. For advanced aerospace materials, which are difficult-to-machine, conventional machining processes cannot meet the requirements of high in-service functional performance owing to rapid tool wear, low processing efficiency and high cutting forces and temperatures in the cutting area during machining.

To address this literature gap, this study is focused on the quantitative evaluation of the in-service functional performance (fatigue performance, wear resistance and corrosion resistance) of advanced aerospace materials. First, the characteristics and usage background of advanced aerospace materials are elaborated in detail. Second, the improved effect of UVC on in-service functional performance is summarized. We have also explored the unique advantages of UVC during the processing of advanced aerospace materials. Finally, in response to some of the limitations of UVC, future development directions are proposed, including improvements in ultrasound systems, upgrades in ultrasound processing objects and theoretical breakthroughs in in-service functional performance.

This study provides insights into the optimization of machining processes to improve the in-service functional performance of advanced aviation materials, particularly the use of UVC and its unique process advantages.

Purpose: Preserving a country’s culture is crucial for its sustainability. Handicraft is a key draw for tourism destinations; it protects any civilisation’s indigenous knowledge and culture by managing the historical, economic, and ecological ecosystems and perfectly aligns with sustainable development. It has a significant role in creating employment, especially in rural regions and is an essential contributor to the export economy, mainly in developing nations. The study focuses on the skills required and existing gaps in the handicraft industry, its development and prospects by considering women and their role in preserving and embodying the traditional art of making handicrafts.

Approach: A framework has been developed for mapping and analysing the skills required in the handicraft sector using econometric modelling; an enormous number of skills have been crowdsourced from the respondents, and machine learning techniques have been used.

Findings: The findings of the study revealed that employment in this area is dependent not only on general or specialised skills but also on complex matrix skills ranging from punctuality to working in unclean and unsafe environments, along with a set of personal qualities, such as taking initiatives and specific skills, for example polishing and colour coding.

Implications: The skills mapping technique utilised in this study is applicable globally, particularly for women indulged in casual work in developing nations’ handicrafts industry. The sustainable development goals, tourism, and handicrafts are all interconnected. The research includes understanding skills mapping, which provides insights into efficient job matching by incorporating preferences and studying the demand side of casual working by women in the handicraft sector from a skills perspective.

Surface acoustic wave (SAW) sensors have attracted great attention worldwide for a variety of applications in measuring physical, chemical and biological parameters. However, stability has been one of the key issues which have limited their effective commercial applications. To fully understand this challenge of operation stability, this paper aims to systematically review mechanisms, stability issues and future challenges of SAW sensors for various applications.

This review paper starts with different types of SAWs, advantages and disadvantages of different types of SAW sensors and then the stability issues of SAW sensors. Subsequently, recent efforts made by researchers for improving working stability of SAW sensors are reviewed. Finally, it discusses the existing challenges and future prospects of SAW sensors in the rapidly growing Internet of Things-enabled application market.

A large number of scientific articles related to SAW technologies were found, and a number of opportunities for future researchers were identified. Over the past 20 years, SAW-related research has gained a growing interest of researchers. SAW sensors have attracted more and more researchers worldwide over the years, but the research topics of SAW sensor stability only own an extremely poor percentage in the total researc topics of SAWs or SAW sensors.

Although SAW sensors have been attracting researchers worldwide for decades, researchers mainly focused on the new materials and design strategies for SAW sensors to achieve good sensitivity and selectivity, and little work can be found on the stability issues of SAW sensors, which are so important for SAW sensor industries and one of the key factors to be mature products. Therefore, this paper systematically reviewed the SAW sensors from their fundamental mechanisms to stability issues and indicated their future challenges for various applications.

Preparing CrAlN coatings on the surface of silicon nitride bearings can improve their service life in oil-free lubrication. This paper aims to match the optimal process parameters for preparing CrAlN coatings on silicon nitride surfaces, and reveal the microscopic mechanism of process parameter influence on coating wear resistance.

This study used molecular dynamics to analyze how process parameters affected the nucleation density, micromorphology, densification and internal stress of CrAlN coatings. An orthogonal test method was used to examine how deposition time, substrate temperature, nitrogen-argon flow rate and sputtering power impacted the wear resistance of CrAlN coatings under dry friction conditions.

Nucleation density, micromorphology, densification and internal stress have a significant influence on the surface morphology and wear resistance of CrAlN coatings. The process parameters for better wear resistance of the CrAlN coatings were at a deposition time of 120 min, a substrate temperature of 573 K, a nitrogen-argon flow rate of 1:1 and a sputtering power of 160 W.

Simulation analysis and experimental results of this paper can provide data to assist in setting process parameters for applying CrAlN coatings to silicon nitride bearings.

The purpose of the study is to perform elastic stress and deformation analysis of a functionally graded hollow disk under different conditions (rotation, gravity, internal pressure, temperature with variable heat generation) and their combinations.

The classical method of solution, Navier's equation, is used to solve the governing equation. The analysis considers thermal and mechanical boundary conditions and takes into account the variation of material properties according to a power law function of the radius of the disk and grading parameter.

The findings of the study reveal distinct trends and behaviors based on different grading parameters. The influence of gravity is found to be negligible, resulting in similar patterns to the pure rotation case. Variable heat generation introduces non-linear temperature profiles and higher displacements, with stress values influenced by grading parameters.

The study provides valuable insights into the behavior of displacement and stresses in hollow disks, offering a deeper understanding of their mechanical response under varying conditions. These insights can be useful in the design and analysis of functionally graded hollow disks in various engineering applications.

The originality and value of this study lies in the consideration of various loading combinations of rotation, gravity, internal pressure and temperature with variable heat generation. Furthermore, the study of effect of various angular rotations, temperatures and pressures expands the understanding of the mechanical behavior of such structures, contributing to the existing body of knowledge in the field.

The purpose is to explore the free vibration behaviour of elastic foundation-supported porous functionally graded nanoplates using the Rayleigh-Ritz approach. The goal of this study is to gain a better knowledge of the dynamic response of nanoscale structures made of functionally graded materials and porous features. The Rayleigh-Ritz approach is used in this study to generate realistic mathematical models that take elastic foundation support into account. This research can contribute to the design and optimization of advanced nanomaterials with potential applications in engineering and technology by providing insights into the influence of material composition, porosity and foundation support on the vibrational properties of nanoplates.

A systematic methodology is proposed to evaluate the free vibration characteristics of elastic foundation-supported porous functionally graded nanoplates using the Rayleigh-Ritz approach. The study began by developing the mathematical model, adding material properties and establishing governing equations using the Rayleigh-Ritz approach. Numerical approaches to solve the problem are used, using finite element methods. The results are compared to current solutions or experimental data to validate the process. The results are also analysed, keeping the influence of factors on vibration characteristics in mind. The findings are summarized and avenues for future research are suggested, ensuring a robust investigation within the constraints.

The Rayleigh-Ritz technique is used to investigate the free vibration properties of elastic foundation-supported porous functionally graded nanoplates. The findings show that differences in material composition, porosity and foundation support have a significant impact on the vibrational behaviour of nanoplates. The Rayleigh-Ritz approach is good at modelling and predicting these properties. Furthermore, the study emphasizes the possibility of customizing nanoplate qualities to optimize certain vibrational responses, providing useful insights for engineering applications. These findings expand understanding of dynamic behaviours in nanoscale structures, making it easier to build innovative materials with specific features for a wide range of industrial applications.

The novel aspect of this research is the incorporation of elastic foundation support, porous structures and functionally graded materials into the setting of nanoplate free vibrations, utilizing the Rayleigh-Ritz technique. Few research have looked into this complex combo. By tackling complicated interactions, the research pushes boundaries, providing a unique insight into the dynamic behaviour of nanoscale objects. This novel approach allows for a better understanding of the interconnected effects of material composition, porosity and foundation support on free vibrations, paving the way for the development of tailored nanomaterials with specific vibrational properties for advanced engineering and technology applications.

This chapter explores the approaches to digital representation of Australian Aboriginal art and visitor engagement in museum exhibition spaces from a digital design perspective. It discusses recent developments in the fields of digital representation of Aboriginal art, immersive exhibition design and visitor engagement. Through a case study of an immersive exhibition on Australian Aboriginal art in the National Museum of Australia, Canberra, this chapter identifies how Aboriginal art can be digitally represented by appropriate immersive technologies ranging from augmented realities [ARs] and virtual realities [VRs] to mixed reality [MRs] and extended reality [XRs] for enhancing visitors’ immersive digital experience. According to the analysis, the digital representation of Aboriginal artworks needs to be conducted practically, cognitively and ontologically based on understanding Australian Aboriginal history and culture. Visitors can engage with Aboriginal art stories meaningfully through immersive exhibitions through this holistic approach.

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.