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Fused filament fabrication (FFF) is one of the most popular additive manufacturing (AM) technologies due to its ability to build thermoplastic parts with complex geometries at low cost. The FFF technique has been mainly used for rapid prototyping owing to the poor mechanical and geometrical properties of pure thermoplastic parts. However, both the development of new fibre-reinforced filaments with improved mechanical properties, and more accurate composite 3D printers have broadened the scope of FFF applications to functional components. FFF is a complex process with a large number of parameters influencing product quality and mechanical properties, and the effects of the combined parameters are usually difficult to evaluate. An array of parameter combinations has been analysed for improving the mechanical performance of thermoplastic parts such as layer thickness, build orientation, raster angle, raster width, air gap, infill density and pattern, fibre volume fraction, fibre layer location, fibre orientation and feed rate. This study aims to assess the effects of nozzle diameter on the mechanical performance and the geometric properties of 3D printed short carbon fibre-reinforced composites processed by the FFF technique.

Tensile and three-point bending tests were performed to characterise the mechanical response of the 3D printed composite samples. The dimensional accuracy, the flatness error and surface roughness of the printed specimens were also evaluated. Moreover, manufacturing costs, which are related to printing time, were evaluated. Finally, scanning electron microscopy images of the printed samples were analysed to estimate the porosity as a function of the nozzle diameter and to justify the effect of nozzle diameter on dimensional accuracy and surface roughness.

The effect of nozzle diameter on the mechanical and geometric quality of 3D printed composite samples was significant. In addition, large nozzle diameters tended to increase mechanical performance and enhance surface roughness, with a reduction in manufacturing costs. In contrast, 3D printed composite samples with small nozzle diameter exhibited higher geometric accuracy. However, the effect of nozzle diameter on the flatness error and surface roughness was of slight significance. Finally, some print guidelines are included.

The effect of nozzle diameter, which is directly related to product quality and manufacturing costs, has not been extensively studied. The presented study provides more information regarding the dependence of the mechanical, microstructural and geometric properties of short carbon fibre-reinforced nylon composite components on nozzle diameter.

The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material wastage. In this study, 316L stainless-steel metal filled filaments were used to print metal parts using the extrusion-based fused filament fabrication (FFF) approach. The purpose of this study is to assess the effects of common FFF printing parameters on the geometric and mechanical performance of FFF manufactured 316L stainless-steel components.

The microstructural characteristics of the metal filled filament, three-dimensional (3D) printed green parts and final sintered parts were analysed. In addition, the dimensional accuracy of the green parts was evaluated, as well as the hardness, tensile properties, relative density, part shrinkage and the porosity of the sintered samples. Moreover, surface quality in terms of surface roughness after sintering was assessed. Predictive models based on artificial neural networks (ANNs) were used for characterizing dimensional accuracy, shrinkage, surface roughness and density. Additionally, the response surface method based on ANNs was applied to represent the behaviour of these parameters and to identify the optimum 3D printing conditions.

The effects of the FFF process parameters such as build orientation and nozzle diameter were significant. The pore distribution was strongly linked to the build orientation and printing strategy. Furthermore, porosity decreased with increased nozzle diameter, which increased mechanical performance. In contrast, lower nozzle diameters achieved lower roughness values and average deviations. Thus, it should be noted that the modification of process parameters to achieve greater geometrical accuracy weakened mechanical performance.

Near-dense 316L austenitic stainless-steel components using FFF technology were successfully manufactured. This study provides print guidelines and further information regarding the impact of FFF process parameters on the mechanical, microstructural and geometric performance of 3D printed 316L components.

Fused filament fabrication (FFF) technique using metal filled filaments in combination with debinding and sintering steps can be a cost-effective alternative for laser-based powder bed fusion processes. The mechanical behaviour of FFF-metal materials is highly dependent on the processing parameters, filament quality and adjusted post-processing steps. In addition, the microstructural material properties and geometric characteristics are inherent to the manufacturing process. The purpose of this study is to characterize the mechanical and geometric performance of three-dimensional (3-D) printed FFF 316 L metal components manufactured by a low-cost desktop 3-D printer. The debinding and sintering processes are carried out using the BASF catalytic debinding process in combination with the BASF 316LX Ultrafuse filament. Special attention is paid on the effects of build orientation and printing strategy of the FFF-based technology on the tensile and geometric performance of the 3-D printed 316 L metal specimens.

This study uses a toolset of experimental analysis techniques [metallography and scanning electron microcope (SEM)] to characterize the effect of microstructure and defects on the material properties under tensile testing. Shrinkage and the resulting porosity of the 3-D printed 316 L stainless steel sintered samples are also analysed. The deformation behaviour is investigated for three different build orientations. The tensile test curves are further correlated with the damage surface using SEM images and metallographic sections to present grain deformation during the loading progress. Mechanical properties are directly compared to other works in the field and similar additive manufacturing (AM) and Metal Injection Moulding (MIM) manufacturing alternatives from the literature.

It has been shown that the effect of build orientation was of particular significance on the mechanical and geometric performance of FFF-metal 3-D printed samples. In particular, Flat and On-edge samples showed an average increase in tensile performance of 21.7% for the tensile strength, 65.1% for the tensile stiffness and 118.3% for maximum elongation at fracture compared to the Upright samples. Furthermore, it has been able to manufacture near-dense 316 L austenitic stainless steel components using FFF. These properties are comparable to those obtained by other metal conventional processes such as MIM process.

316L austenitic stainless steel components using FFF technology with a porosity lower than 2% were successfully manufactured. The presented study provides more information regarding the dependence of the mechanical, microstructural and geometric properties of FFF 316 L components on the build orientation and printing strategy.

Non-uniform rational B-splines (NURBSs) are the de facto standard for representing objects in computer-aided design (CAD). The purpose of this paper is to discuss how to stick to this standard in all phases of the additive manufacturing (AM) workflow, from the CAD object to the final G-code, bypassing unnecessary polygonal approximations.

The authors use a commercial CAD system (Rhino3D along with its programming environment Grasshopper) for direct slicing of the model, offset generation and trimming. Circular arcs are represented as quadratic NURBSs and free-form geometry as quadratic or cubic polynomial B-splines. Therefore, circular arcs are directly expressible as G2/G3 G-code commands, whereas free-form paths are rewritten as a succession of cubic Bézier curves, thereby admitting exact translation into G5 commands, available in firmware for AM controllers, such as Marlin.

Experimental results of this paper confirm a considerable improvement in quality over the standard AM workflow, consisting of an initial polygonization of the object (e.g. via standard tessellation language), slicing this polygonal approximation, offsetting the polygonal sections and, finally, generating G-code made up of polyline trajectories (G1 commands).

A streamlined AM workflow is obtained, with a seamless transfer from the initial CAD description to the final G-code. By adhering to the NURBS standard at all steps, the authors avoid multiple representations and associated errors resulting from approximations.

This paper investigates the relationship between teleworkers' perceptions of corporate social responsibility (CSR) and employee engagement (EE) in remote work.

A quantitative research approach was used, involving a questionnaire distributed via convenience sampling. Data from 205 valid responses from teleworking employees in Spain were analysed using structural equation modelling to test the hypothesis regarding the association between CSR and EE.

The study found that CSR’s social and environmental dimensions positively impact EE among teleworkers. However, the economic dimension of CSR only partially influences EE in a telework setting.

The findings suggest organisations can enhance EE during telework periods by focusing on social and environmental CSR initiatives. This approach can mitigate the reduced EE associated with remote work, improving organisational performance, productivity, satisfaction and employee well-being.

This study provides empirical evidence on the positive effects of CSR’s social and environmental dimensions on EE in a telework context, offering valuable insights for organisations navigating the post-pandemic landscape. Also, specific CSR strategies can establish a competitive advantage by fostering a motivated and engaged remote workforce.

Este artículo investiga la relación entre las percepciones de los teletrabajadores sobre la responsabilidad social corporativa (RSC) y el compromiso de los empleados (EE) en el trabajo remoto.

Se utilizó un enfoque de investigación cuantitativa, mediante un cuestionario distribuido a través de un muestreo por conveniencia. Se analizaron datos de 205 respuestas válidas de empleados teletrabajadores en España utilizando modelos de ecuaciones estructurales para probar la hipótesis sobre la asociación entre RSC y EE.

El estudio encontró que las dimensiones sociales y ambientales de la RSC impactan positivamente en el EE entre los teletrabajadores. Sin embargo, la dimensión económica de la RSC solo influye parcialmente en el EE en un entorno de teletrabajo.

Los hallazgos sugieren que las organizaciones pueden mejorar el EE durante los períodos de teletrabajo al enfocarse en iniciativas de RSC social y ambiental. Este enfoque puede mitigar la reducción del EE asociada con el trabajo remoto, mejorando el rendimiento organizacional, la productividad, la satisfacción y el bienestar de los empleados.

Este estudio proporciona evidencia empírica sobre los efectos positivos de las dimensiones sociales y ambientales de la RSC en el EE en un contexto de teletrabajo, ofreciendo valiosas ideas para las organizaciones que navegan el paisaje post-pandémico. Además, estrategias específicas de RSC pueden establecer una ventaja competitiva al fomentar una fuerza laboral remota motivada y comprometida.

Sterilization is endorsed as a method of family planning by international governmental organizations; abortion is not. Focusing on policy development for these two issues in a single country, Peru, we ask how power and inequality operate under conditions of global consensus or dissensus. The case of sterilization unfolded the way many previous research studies would predict, with Peruvian state actions corresponding to a global diffusion process. We find that global consensus provided cover for top-down actions that violated the human rights of indigenous women in the country, who were predominantly poor, non-Spanish speakers, and residents of the mountainous, sparsely populated parts of the country. With respect to abortion in Peru, in the absence of global consensus, the state resisted calls for change, advocacy networks have worked at cross-purposes, and a powerful local actor, the Catholic Church, has effectively blocked liberalization efforts. As with sterilization, however, marginalized indigenous women and their interests were rendered invisible.

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

3D printing techniques such as material extrusion based additive manufacturing provide a promising and cost effective manufacturing technique. However, the main challenges in industrial applications remain with the quality assurance of mass produced parts. The purpose of this study is to investigate the effect of compression moulding as a rapid consolidation method for 3D printed composites, with an aim to reduce voids and defects and thus improving quality assurance of printed parts.

To develop an understanding of the inherent voids in 3D parts and the influence on mechanical properties, material extrusion additively manufactured (MEX) parts were post consolidated by using compression moulding at elevated temperature.

This study comparatively investigates the influence of carbon fibre length, undergoing process induced scission during filament extrusion and IM and its impact on void content and mechanical properties. It was found that the post consolidation significantly reduced the voids and the mechanical properties were significantly improved compared to the nonconsolidated material extrusion additively manufactured parts, reaching values similar to those of the IM parts.

Adaptation of extrusion-based additive manufacturing with hybridisation of reliable compression moulding technology transcends into series production of highly adaptive end user applications, such as drones, advanced sports prosthetics, competitive cycling and more.

This paper adds to the current understanding of 3D printing and provides a step towards quality assurance for mass production.