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- Study of Laser Metal Deposition (LMD) as a Manufacturing Technique in Automotive IndustryPublication . Quaresma Ramalho, Francisco Miguel; Alves, M.L.; Correia, M. S.; Vilhena, L. M.; Ramalho, A.The last few decades in the automotive industry have been marked by a heavy concern with the environment, saving energy and reducing material wastage, while aiming to maintain good mechanical properties, essential in the components usage. Additive manufacturing (AM) techniques present themselves as a viable option in the matter, with Laser Metal Deposition (LMD), rising as one of the most promising techniques within this category, capable of producing near-net shape components, with a layer upon layer construction of three-dimensional solid parts from a 3D CAD model, with good mechanical properties and acceptable surface finishing. Laser Metal Deposition is a relatively recent technique, which is made noticeable by the lack of clarification about the influence of several parameters in the final components characteristics, ultimately leading to a scarce availability of the process in the market. This paper aims to clarify and evaluate, how LMD produced parts can suit the automotive industry, by measuring and analysing their behaviour under several mechanical tests. These mechanical tests have specific focus on wear and abrasion behaviour, as well as elastic properties determination, as these are the characteristics that allow a better overview over the expected performance of LMD components for automotive applications.
- Morphology and Thermal Behaviour of New Mycelium-Based Composites with Different Types of SubstratesPublication . Alves, Rafael M. E.; Alves, M.L.; Campos, Maria J.The need for new green and sustainable materials has been fostering the development, research and introduction of biodegradable materials from natural and renewable sources. Commercially available biodegradable plastics, while minimizing their environmental impact and exhibiting a set of properties that enable the obtainment of industrial components, usually require complex processing methods, are costly and have limited applicability. A new growth of natural resources based paradigm applied as production process is increasing its relevance as an alternative production process. New materials that combine fungal mycelium with waste materials as coffee grounds or wood waste can be considered as promising to fulfill this new paradigm. This new biomaterial mycelium based composites present controllable and adjustable properties during their growth, being able to grow and penetrate organic substrates, thus forming a tangle of branched fibers and a structure that presents some thermo-mechanical properties similar to the ones of plastics. The aim of the present study was the selection of the optimal inoculation temperature, light, humidity and the best substrate for the fastest and consistent mycelium growth. Four types of mycelium were incubated, namely Pleurotus ostreatus (382), Hypsizygus ulmarius (420), Ganoderma lucidum (560) and Trametes versicolor (620). The influence of the three substrates (coffee grounds, pine waste and general wood waste) on the growth was analyzed both morphologically and thermo-mechanically by means of differential scanning calorimetry (DSC) and X-ray micro computed tomography (microCT).
- Moving Forward to 3D/4D Printed Building FacadesPublication . Craveiro, Flávio; Duarte, José P.; Bártolo, Helena; Bártolo, PauloNearly Zero Energy Buildings will require high-performance building envelopes, though the building sector is currently a major contributor to the world’s energy consumption and related CO2 emissions. Innovative advanced materials, such as smart or functionally graded materials are being developed to better adapt buildings to environmental needs. This paper presents a brief overview of novel advanced materials for passive/kinetic facades. There is a great potential for 3D/4D printing building components to address actual and future built environmental challenges. 3D printing buildings are still in its infancy, several limitations and barriers need to be addressed, though architects and engineers must keep looking forward and the rise of 4D design could bring “life” to buildings.