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This study aims to make foamed polylactic acid (PLA) structures with different densities by varying deposition temperatures using the material extrusion (MEX) additive manufacturing process.

The extrusion multiplier (EM) was calibrated for each deposition temperature to control foaming expansion. Material density was determined using extruded cubes with the optimal EM value for each deposition temperature. The influence of deposition temperature on the tensile, compression and flexure characteristics of the foamable filament was studied experimentally.

The foaming expansion ratio, the consistency of the raster width and the raster gap significantly affect the surface roughness of the printed samples. Regardless of the loading conditions, the maximum stiffness and yield strength were achieved at a deposition temperature of 200°C when the PLA specimens had no foam. When the maximum foaming occurred (220°C deposition temperature), the stiffness and yield strength of the PLA specimens were significantly reduced.

The obvious benefit of using foamed materials is that they are lighter and consume less material than bulky polymers. Injection or compression moulding is the most commonly used method for creating foamed products. However, these technologies require tooling to fabricate complicated parts, which may be costly and time-consuming. Conversely, the MEX process can produce extremely complex parts with less tooling expense, reduction in energy use and optimised material consumption.

This study investigates the possibility of stiff, lightweight structures with low fractions of interconnected porosity using foamable filament.

High silicon Si–Al alloys (50–70 wt% Si) have been developed by Osprey Metals Ltd for use in electronic packaging. They have the advantages of a coefficient of thermal expansion that can be tailored to match ceramics and electronic materials (6–11 ppm/K), low density (<2.8 g/cm³) high thermal conductivity (>100 W/m K). These alloys are also environmentally friendly and are easy to recycle.These Osprey alloys can be fabricated readily into electronic packages by conventional machining with tungsten‐carbide or polycrystalline diamond (PCD) tools and electro‐discharge machining (EDM). Generally more than one of these conventional machining operations is required in the fabrication process. A new and much faster method has been developed which has been used to produce complete electronic packages from plates of Si–Al alloys in a single machining step. In this novel method, known as thin‐shell electroforming (TSE), an accurate model of the package is produced directly from the drawing in wax using a 3D Systems ThermoJet Modeller. This model is mounted into a frame and it is then plated with a thin copper electroform. The wax model is then melted leaving the electroform attached to the frame. This is backfilled with solder and used as the EDM tool for machining the package from a plate of Si–Al alloy.

Due to the Coronavirus 2019 (COVID-19) pandemic, education has been disrupted right from kindergarten to University. Globally, states are advocating for online learning. The COVID-19 pandemic had led to the closure of universities and it was not clear how long this would last. e-Learning was crucial. Lecturers were asked to complete their syllabuses and continue to teach and administer tests remotely. So far, there is a dearth of information on how Kenya’s higher education responded to the pandemic through online learning. This qualitative study utilized online platforms (zoom and Skype) for interviews. This study employed a constructivist approach to explore the faculty officials’ perception of online learning in Kenya’s institutions of higher education. Approximately 45 faculty officials from public universities were involved in this study. The study was carried out in three public universities in Western Kenya. The participants argued that online education was beneficial and primarily promoted online research and enabled them to connect with other practitioners in the global community. There were challenges associated with online learning for instance unreliable internet. This study’s results are hoped to inform the ministry of education and higher learning policies on making online effective and efficient to both the students and the lecturers. This will also be a fairer spring-ball for Kenya toward the realization of Vision 2030.

The purpose of this paper is to produce electric discharge machining (EDM) electrodes by using stereolithography (SLA) rapid prototyping technique and investigate the machining performance of these electrodes. In the experimental part of the study, the performance of solid copper and copper‐coated SLA (cc/SLA) electrodes are observed and compared.

The performance outputs such as material removal rate, machining depth, workpiece surface roughness and electrode front surface wear are used as metrics of comparison. The temperature measurements taken from the face of both solid copper and cc/SLA electrodes indicated that the heat build up during machining significantly accelerated the failure of cc/SLA electrodes.

The paper finds that circulating the cooling liquid inside the internal cooling channels formed with SLA technique, elongated the life of cc/SLA electrodes by dissipating the heat from the coating.

The Fluent Computational Fluid Dynamics (CFD) Software is used to numerically analyze various aspects of cooling of cc/SLA electrodes. The key findings of the study are presented in this paper.

Cu‐ZrB₂ shell electrodes were fabricated by composite electroforming to improve the spark‐resistance of the electrical discharge machining (EDM) electrodes made by rapid tooling.

Cu‐ZrB₂ shell electrodes were fabricated using composite electroforming, separating and backing. EDM performance evaluation of the Cu‐ZrB₂ shell electrodes is performed using tool steel as the cathode workpiece and the Cu‐ZrB₂ composite as the anode tool. The effects of ZrB₂ content on the electrode and workpiece removal rate, wear ratio of the electrode to workpiece, and surface quality of workpiece and electrode were studied.

Compared with the conventional electroformed copper tools, Cu‐ZrB₂ shell electrodes yield higher workpiece removal rate and lower tool wear ratio. Scanning electron microscopy (SEM) and electron microprobe analysis reveal that, due to the large difference between the melting point of ZrB₂ and copper, the heat generated by the sparks is conducted mainly through the copper matrix, reducing the erosion of ZrB₂ particles. The refractory ZrB₂ particles then act as barriers to the flowing and outburst of melted copper and enhance the resistance to erosion of the electrodes.

The use of Cu‐ZrB₂ shell electrodes improves the anti‐erosion properties of the EDM electrodes made by rapid tooling, especially in finish machining conditions. Such electrodes will not only reduce the failure of the EDM electrodes but also improve the machining precision due to the less dimension loss of the electrodes during machining.

The paper aims to explore the potential for using 3D printing technology as a more sustainable tool in various areas of the tourism and hospitality industry in Cyprus.

For the purpose of this study, qualitative research was conducted to explore the potential for 3D printing technology deployment in Cyprus and specifically in tourism and hospitality settings. Interviews were conducted with industry professionals and practitioners using a snowball sampling method.

The tourism and hospitality industry currently uses 3D printing technology mainly to assist with the restoration of cultural heritage, sites but there is significant potential to implement 3D printing more widely in support of other building work, souvenirs and food items.

The paper explores current applications and the wider potential for using 3D technology in building, restoration of cultural heritage, souvenirs and food-related printing that together could contribute to a more sustainable tourism and hospitality industry in Cyprus.

This study aims to analyze the effect of the different common post-processes on the geometrical and dimensional accuracy of selective laser melting (SLM) parts.

An artefact has been designed including cubic features formed by planar surfaces orientated according to the machine axes, covering all the X-Y area of the working space. The artefact has been analyzed both geometrically (flatness, parallelism) and dimensionally (sizes, distances) from coordinate measuring machine measurement results at three stages, namely, as-built, after sand-blasting and after stress-relieving heat treatment.

Results from the SLM machine used in this study lead to smaller parts than the nominal ones. This effect depends on the direction of the evaluated dimension of the parts, i.e. X, Y or Z direction and is differently affected by the sandblasting post-process (average erosion ratio of 68, 54 and 9 µm, respectively), being practically unaltered by the HT applied after.

This paper shows the influence, from a geometric and dimensional point of view, of two of the most common post-processes used after producing SLM parts, such as sand-blasting and stress-relieving heat treatment, that have not been considered in previous research.

This study aims to explore the potential benefits favoring the adaptation of structural optimization techniques in the additive manufacturing (AM) of medical utilities to meet the repetitive demand for functionally precise customized orthoses. Irregularities encountered during the conventional treatment of tendon injuries can be eschewed using advanced structural simulation in design and innovative splint fabrication using 3D printing.

A customized mallet finger splint designed from 3D scans was subjected to ANSYS topological simulation comprising multi-level weight reduction to retain optimal mass (100%, 90%, 80%, 70% and 60%). A batch of the four typical 3D printing materials was chosen to conduct a comparative mechanical and thermal stress analysis, facilitating the selection of the optimal one for fabricating functionally adaptive splints. Assurance of structural safety was accomplished through the experimental validation of simulation results against the testing data set of ASTM D695 and ASTM D638 Type-1 specimens over a universal testing machine (UTM). Fused deposition modeling (FDM) 3D printing processed the optimized splint fabrication to assist evaluation of weight reduction percentage, fitting aesthetics, appearance, comfort, practicality and ventilation ease at the user end.

AM efficacy can efficiently execute the design complexity involved in the topology optimization (TO) results and introduces rehabilitation practicality into the application. Topologically optimized splint provided with favorable comfort, stiffness and strengthening features, offers ventilation ease and structural stability for customized appliances, with 30.52% lighter weight and 121.37% faster heat dissipation than unoptimized one.

The state of art multidisciplinary optimization featured with structural and material optimization attributes can deliberately meet medical necessity for performance-oriented orthotic devices.