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The performance of parts produced by fused filament fabrication is directly related to the printing conditions and to the rheological phenomena inherent to the process, specifically the bonding between adjacent extruded paths/raster. This paper aims to study the influence of a set of printing conditions and parameters, namely, envelope temperature, extrusion temperature, forced cooling and extrusion rate, on the parts performance.

The influence of these parameters is evaluated by printing a set of test specimens that are morphologically characterized and mechanically tested. At the morphological level, the external dimensions and the voids content of the printed specimens are evaluated. The bonding quality between adjacent extruded paths is assessed through the mechanical performance of test specimens, subjected to tensile loads. These specimens are printed with all raster oriented at 90º relative to the tensile axis.

The best performance, resulting from a compromise between surface quality, dimensional accuracy and mechanical performance, is achieved with a heated printing environment and with no use of forced cooling. In addition, for all the conditions tested, the highest dimensional accuracy is achieved in dimensions defined in the printing plane.

This work provides a relevant result as the majority of the current printers comes without enclosure or misses the heating and envelope temperature control systems, which proved to be one of the most influential process parameter.

This work aims to provide additional insights regarding the practicability of using conventional materials in the fused filament fabrication (FFF) process.

Two different acrylonitryle butadiene styrene (ABS) grades are studied and compared, aiming to check to what extent the regular ABS developed for conventional polymer processing, with a different rheology than the one provided for the FFF process, can also be used in this process (FFF).

The rheological results show that a general-purpose ABS (ABS-GP) melt is much more viscous and elastic than ABS-FFF. It is clear that using ABS-GP as feedstock material in the FFF process results in poor coalescence and adhesion between the extruded filaments, which has a detrimental effect on the mechanical properties of the printed specimens. Despite its lower performance, ABS-GP can be a good choice if the objective is to produce an aesthetical prototype. If the objective is to produce a functional prototype or a final part, its mechanical performance requirements will dictate the choice.

This work provides insightful information regarding the use of high viscosity materials on the 3D printing process.

An issue when printing multi-material objects is understanding how different materials will perform together, especially because interfaces between them are always created. This paper aims to address this interface from a mechanical perspective and evaluates how it should be designed for a better mechanical performance.

Different interface mechanisms were considered, namely, microscopic interfaces that are based on chemical bonding and were represented with a U-shape interface; a macroscopic interface characterized by a mechanical interlocking mechanism, represented by a T-shape interface; and a mesoscopic interface that sits between other interface systems and that was represented by a dovetail shape geometry. All these different interfaces were tested in two different material sets, namely, poly (lactic acid)–poly (lactic acid) and poly (lactic acid)–thermoplastic polyurethane material pairs. These two sets represent high- and low-compatibility materials sets, respectively.

The results showed, despite the materials’ compatibility level, multi-material objects will have a better mechanical performance through a macroscopic interface, as it is based on a mechanical interlocking system, of which performance cannot be achieved by a simple face-to-face interface even when considering the same material.

The paper investigates the importance of interface design in multi-material 3D prints by fused filament fabrication. Especially, for parts intended to be subjected to mechanical efforts, simple face-to-face interfaces are not sufficient and more robust and macroscopic-based interface geometries (based on mechanical interlocking systems) are advised. Moreover, such interfaces do not raise esthetic problems because of their working principle; the 3D printing technology can hide the interface geometries, if required.

The purpose of this paper is to address the gaps in research on strategic planning for the social impacts of small-scale events in rural areas and small cities. This is achieved by investigating the social utility inferred by small-scale art festivals with a creative tourism element in terms of increasing social capital and positive social change, from an event stakeholder perspective.

The identified gap in knowledge is addressed by using interviews and fieldnotes from participant observation to co-create meaning with the organizers of four small-scale art festivals in small cities and rural areas in Portugal. Theoretical frameworks relating to creative tourism development and social capital creation are used to analyze the social utility of small-scale art festivals.

Creative tourism activities are integrated within small-scale art festivals in small cities and rural areas in various ways, mainly through art-related workshops. Significant empirical data give insight into how small-scale art festivals create social value by increasing the host community’s pride and reinforcing the social fabric of the festival’s local and “portable” community, in part through these creative tourism activities.

One of the limitations of this study is that it focuses on the perspectives and insights of the festival organizers. An analysis of the festival participants’ views, local community stakeholder analysis and community impact analyses would offer further insights into how the creative tourism experiences and other moments of shared meaning generation within small-scale art festivals influence the creation of social utility.

This paper offers insights into how creative tourism activities are being integrated into small-scale art festivals in small cities and rural contexts, and how these activities foster social connections among festival participants and with the local community. This addresses significant gaps in the literature on strategic planning for the social impacts of events, particularly in the context of small-scale events in rural areas/small cities, and the strategic value of including creative tourism activities within small-scale festivals.