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Additive manufacturing has a great potential since it allows the production of objects with complex geometries, often without auxiliary tools, while still using a wide range of materials. An example is Fused Filament Fabrication (FFF), one of the technologies frequently referred to as 3D printing. One of the most widely used thermoplastic material in FFF is poly(lactic acid) (PLA). This polymer has superior mechanical properties compared to common polymers, in particular the modulus of elasticity, becoming a good substitute in agricultural applications and packaging. However, in sectors such as automotive and electronics, the application of PLA has some disadvantages, such as: low thermal resistance; low thermal deflection temperature; low crystallization rate and reduced impact resistance. With the rising demand for 3D printing solutions, especially for small size parts with specific properties, the development of new materials to suit those demands became of the utmost importance. Thus, one solution that has been adopted in recent years is the incorporation of nanoparticles in the thermoplastics. In this paper, an experimental setup was developed regarding the processing and characterization of two sets of PLA nanocomposites, one with carbon nanotubes (CNT) and another with graphene. The processed nanocomposites’ properties were tested through mechanical and melt flow index characterizations to study their suitability for 3D printing.

Additive Manufacturing (AM) is the forefront of advanced manufacturing technologies and has the potential to revolutionize manufacturing, with a dramatic change in the design and project paradigms. A comprehensive review of existent metal AM processes, processable materials, respective defects and inspection methods (destructive and non-destructive) is presented in a succinct manner. Particularly, the AM design optimization methodologies are reviewed and their threats and constraints discussed. Finally, an aerospace industry case study is presented and several cost-effective examples are enumerated.

The development of vital competencies and a mindset to rethink products, production, and business models in engineering and design students is presently of great importance. These future professionals will play a key role in the development of sustainable products. Within Eco-design and Eco-efficiency curricular unit, an assignment was developed that consisted of the development of an eco-design and eco-efficiency study of a given product, provided by a real industrial company. In this paper, the challenge description and application are reported, as well as the key conclusions.

With the emergence of flexible/stretchable electronics, flexible solar cells (SCs) are able to attract much academic and industrial attention due to its advantages of lightweight, foldability, low cost, and extensive applications. Wearable technology has become a hot topic in the tech industry in this few years, shirts that read wearer’s biological and physiological information are just beginning to make their way into society and will change the way that we interact with technology. The high strength and good electronic properties of graphene fiber make it a good candidate for some specific applications, such as wearable SCs, since it can be obtained at relatively low cost and it is amongst the strongest commercial yarns in existence. In this review, a summarized state of the art regarding wearable SCs is presented including several applications of graphene and its derivatives with their remarkable unconventional applications.

Photovoltaics is amongst the most important technologies for renewable energy sources, and plays a key role in the development of a society with a smaller environmental footprint. Key parameters for solar cells are their energy conversion efficiency, their operating lifetime, and the cost of the energy obtained from a photovoltaic system compared to other sources. The optimization of these aspects involves the exploitation of new materials and development of novel solar cell concepts and designs. Both theoretical modeling and characterization of such devices require a comprehensive view including all scales from the atomic to the macroscopic and industrial scale. The different length scales of the electronic and optical degrees of freedoms specifically lead to an intrinsic need for multiscale simulation, which is accentuated in many advanced photovoltaics concepts including nanostructured regions. Therefore, multiscale modeling has found particular interest in the photovoltaics community, as a tool to advance the field beyond its current limits. In this article, we review the field of multiscale techniques applied to photovoltaics, and we discuss opportunities and remaining challenges. © T. Abu Hamed et al., published by EDP Sciences, 2018., European Cooperation in Science and Technology: MP1406, The authors are grateful for the financial support by the COST Action MP1406 “MultiscaleSolar.”

True excellence in higher education, namely in engineering, is a difficult concept to define and attain. Engineering programs tend to value the later years as the most important in terms of training and scientific depth, while the first years are relatively neglected. At the same time, there is still a tendency to look at teachers’ achievements in terms of research and knowledge, detached in a certain way from pedagogy. On the contrary, more focus should be put into analysing the profile of teachers and its adequacy to the different approaches needed across the years and course units of a master program. Added to this, are the distinct “perceived realities” between (i) what teachers see as a satisfactorily provided service, (ii) what students need and feel to be the quality of the learning experience, and (iii) what society expects (and will expect, in the future) from engineers. Different views and different alignments, from different stakeholders, require careful assessment and analysis, since the quality of the teaching and learning (as assumed in this study) is strongly related to an individual (or group) perception. In this paper, a methodology is introduced that involves the main stakeholders in defining the quality of teaching and learning, focused on the first year of engineering courses at the University of Aveiro (Portugal). For this, a set of meetings and discussion forums provided the required context for identifying attributes of the mentioned “perceived quality”. As an outcome, a new model is presented, inspired in methodologies usually applied within the field of product design and development. The first layer of results is presented, together with a preliminary analysis and discussion. Future steps towards the goal of defining the best profile of higher education teachers for achieving (a higher level of) excellence in engineering education are also indicated.

Zinc oxide (ZnO) is a wide band gap (~3.37 eV) semiconductor. Thin film ZnO has many attractive applications in optoelectronics and sensors. Recently, nanostructured ZnO (e.g. ZnO quantum dot) has been demonstrated as a hyperbolic material; its dielectric function has opposite signs along different crystal axes within the mid-infrared, making it an interesting material for metamaterials and nanophotonics. Conventional sputtering deposition usually leads to the formation of polycrystalline ZnO films with randomly oriented grains and rough surface. This work demonstrated a solution-based process to grow ZnO thin films with highly oriented nanocrystals. Low-temperature plasmas were employed to modulate the microstructure and optical properties of the films. Such highly anisotropic nanostructured transparent semiconductor films may lead to interesting material properties in developing new optoelectronic devices.

Results of the preparation and characterization of graphene oxide–optical fiber coatings will be presented, considering its potential use for sensing applications. The coatings were deposited using the electrostatic self–assembly method, considering different parameters (average sheet size of the graphene oxide colloidal solutions, the number of the deposited layers and the coating methodology) and characterized through SEM and Raman analyses. Aiming to explore this scheme for sensing applications, graphene oxide-coated tilted fiber Bragg gratings were characterized to refractive index variations. An improvement on the sensitivity was obtained and this result suggests that this could be a promising research field for the development of a new line of sensors.

Shape memory polyurethanes (SMPUs) are thermally activated shape memory materials, which can be used as actuators or sensors in applications including aerospace, aeronautics, automobiles or the biomedical industry. The accurate characterization of the memory effect of these materials is therefore mandatory for the technology’s success. The shape memory characterization is normally accomplished using mechanical testing coupled with a heat source, where a detailed knowledge of the heat cycle and its influence on the material properties is paramount but difficult to monitor. In this work, fiber Bragg grating (FBG) sensors were embedded into SMPU samples aiming to study and characterize its shape memory effect. The samples were obtained by injection molding, and the entire processing cycle was successfully monitored, providing a process global quality signature. Moreover, the integrity and functionality of the FBG sensors were maintained during and after the embedding process, demonstrating the feasibility of the technology chosen for the purpose envisaged. The results of the shape memory effect characterization demonstrate a good correlation between the reflected FBG peak with the temperature and induced strain, proving that this technology is suitable for this particular application.

The goal of the research presented in this chapter is to study and develop an alternative methodology to produce painted chrome-plated polymer parts required by the automotive industry. Nowadays the automotive industry is substituting metal parts for plastic ones. However, these new plastic parts must detain the aesthetic and the main properties of the metal components, i.e. the metallic appearance is of utmost importance, as well as the “cold sensation” of metal.

The concept of Smart City comprises many levels of development, quality of life and wellbeing. One of the key aspects of this idea is the relevance of the overall education of citizens, on technical competences as well as responsible citizenship. Within the innovation-focused drive to future cities, scientific literacy is paramount, particularly considering engineering education. This is noteworthy for the education of today's students, preparing them for life in tomorrow's multifaceted technology-driven world, and directing them to personal and professional development within scientific careers. This Chapter describes the challenges and opportunities of education within today's society paradigms, with an eye on the Smart Cities of the future. A new, innovative and connected approach is presented, with concepts that encompass the main stakeholders in the scientific education system along with the main actors in society. A global and scalable education framework model is detailed, aiming to provide guidelines for an improved collaborative approach to STEM education in the future.

The goal of the Methodologies for Engineering Learning and Teaching (MELT) approach is to enhance the attractiveness of education through science, technology, engineering and mathematics subjects, while promoting awareness of STEM careers during upper secondary school. As a consequence, its main goal is to take into account students' aspirations and expectations during university programs and beyond, leading to an increased engagement in STEM careers. To accomplish these goals, a new, innovative and connected approach is presented, with a concept that encompasses the main stakeholders in scientific education, along with the main actors in society. A global and scalable education framework model is presented, aiming to provide guidelines for an improved collaborative approach to STEM education in the future.

This paper describes a model (and the respective guidelines) for the creation of a debate “think-tank” around the thematic of Engineering Education. From this initiative, a first outcome is obtained, in the form of the Engineering Education Forum 2016 (EEF 2016). The Engineering Education Forum is therefore intended to be a place of discussion and debate on this thematic. The model behind Forum encompasses different approaches and tendencies, looking at the past, analysing the present and discussing the future. From the EEF 2016, several outputs and outcomes can be obtained and used for future strategies on Engineering Education. They are presented in this work, the first one focusing on preliminary quantitative results, regarding both the profiles of involved stakeholders and the responses of participants to a number of challenges proposed to the participants of the “face-to-face” debate. The second group of outcomes is related to qualitative aspects, such as the sessions' content and debates, as well as hints for future initiatives following the EEF model.

The cultivation of sugarcane and production of its derivatives are closely linked to Brazil’s history and development. The factory managers face the problem of discarding the sugarcane bagasse ash (SBA), as these ashes are the final waste resulting from the industrial processes, with no possibility to reduce it. The objective of this study is to analyze the effect of adding SBA to compressed earth blocks (CEBs). Two sets of blocks were prepared with 6% and 12% of cement in addition to the earth and with the addition of SBA at ratios of 0%, 2%, 4% and 8% each. Compressive strength and absorption tests were performed on the blocks. Additionally, masonry prisms were produced with the set of blocks that showed the best preliminary test results. The results showed that the SBA can be incorporated into the CEBs and masonry without damage to the mechanical properties.

In this paper, we employ the Taguchi method to optimise our newly developed time-modulated chemical vapour deposition (TMCVD) process. TMCVD can be used to deposit smoother, nanocrystalline diamond (NCD) coatings onto a range of substrate materials. The implementation of the Taguchi method to optimise the TMCVD process can effectively save valuable time, considerable effort and money, this being the major advantage of the method. The Taguchi method significantly reduces the number of experiments required to optimise a fabrication process. In this study, we investigate the effect of five TMCVD process parameters on five key factors of the as-grown samples. Each parameter was varied at four different values (experimental levels). The 5 considered parameters, taking into consideration the experimental levels, were optimised after performing only 16 experiments. The as-grown films were characterised for hardness, quality, surface roughness and microstructure using SEM, Raman spectroscopy, surface profilometry and Vickers hardness testing.

In recent years, the coating of fiber Bragg gratings (FBGs) with a specific material has opened up the possibility to broaden the limits of applicability of this technology. Diamond has a set of properties that makes it an attractive candidate to protect the optical fiber against chemically harsh environments, whose sensing is also a great challenge. One of the most used techniques to obtain these coatings is through the hot filament chemical vapor deposition (HFCVD); in this process, the temperature reaches, typically, around 850°C-900°C. In this work, the regeneration of a seed FBG during its coating with a nanocrystalline diamond thin film through the HFCVD process is presented. Simultaneously, the thermal monitoring of the process was also performed using the same grating. The resistance test in a corrosive medium reveals an improvement on the durability of the sensing properties of the diamond-coated FBG compared with an uncoated FBG, foreseeing a vast range of applications.

Nanotechnology describes the characterization, fabrication and manipulation of structures, devices or materials that have one or more dimensions that are smaller than 100 nanometers. This area has established itself as a key enabling technology for a wide range of applications, thus becoming a top priority for science and technology policy development, being already used in hundreds of products among the industrial sector, namely, electronic, healthcare, chemical, cosmetics, composites and energy. Despite the development in this area, there are some obstacles to a greater impact of nanotechnology in industry. The lack of information concerning this scientific area, the possibility of adverse impacts of nanotechnology on the environment, human health, safety and sustainability, are still a challenge. This article intends to briefly the prototypes being developed with in the CarbonIspired 2.0 consortium, given with them examples of practical applications, security issues and market challenges in order to an effective collaboration between the academies, research centers and the industrial sector.

Injection molding is, nowadays, a well known and wildly used manufacturing process to produce both thermoplastic and thermosetting polymeric material components, in a large scale, with accuracy and at low prices. Even though the electronics industry provides an economy of scale for the silicon industry, polymer devices can be produced in huge volumes maintaining the requested features and quality, with a great variety of material characteristics, a fact that has considerably open the market to injection molding of microcomponents.

The inscription of a Fibre Bragg Grating (FBG) in optical fibres allows them to be used as sensors, being capable of decoding small variations of strain; temperature; pressure; loading; bending; or even refractive index, by means of a shift in the reflected wavelength. Nevertheless, broadening their sensitivity and operation range would be desirable. This may be achieved by appropriated fibre coating. Diamond possesses a set of extreme properties, such as high thermal conductivity, hardness and resistance to hazard environments. Furthermore, it is known for its excellent biocompatible response, so it may be suitable to be used as a coating material for biological sensors. In this paper, the results of the optimization process of diamond coatings on optical fibre sensors is presented, considering their potential use for practical biological purposes.

Dielectric thin films of high- and low-refractive index are the essential components for optical coatings. To achieve high sputtering rates and superior film quality, the authors have developed novel conductive SiO2:Si and ZnO:Zn composites that become conductive once the doped silicon and metal Zn reach a critical ratio. The sputtering characteristics of the composite targets in direct current and radio-frequency (RF) plasma discharge are quite different from the corresponding element targets. The optical properties of the RF sputtered SiO2 and ZnO films from the composite targets is comparable with the films obtained from RF sputtering of pure oxide targets.