Papers by Keyword: Advanced Materials

Abstract: The transition to hydrogen-based energy systems presents a critical need for materials capable of withstanding the harsh conditions of hydrogen storage. Our project addresses this challenge by developing a multilayer steel designed specifically for hydrogen environments. This material combines austenitic steel, known for its resistance to hydrogen embrittlement, with carbon steel, which provides strength and cost efficiency. Hydrogen embrittlement poses a well-known issue in the storage and transport of hydrogen, often degrading various metals. Although many stainless steels provide superior resistance, its high-cost limits widespread application. Our solution involves a multilayer approach, where austenitic layer serves as the primary barrier against hydrogen-induced degradation, and the carbon steel layer ensures the material’s structural strength under high pressure. The manufacturing process involves hot roll bonding, where the surfaces of the two materials are cleaned of oxides, welded together, heated up to 1200 °C, and then hot rolled to form a strong bond. This method not only strengthens the material but also makes it a potential solution for large-scale hydrogen storage applications.

Abstract: This paper introduces a novel fatigue failure criterion that leverages the evolution of residual stresses under cyclic loading to more accurately predict fatigue life in advanced materials. Traditional fatigue models often overlook the dynamic nature of residual stresses, which can significantly influence crack initiation and propagation. The proposed criterion incorporates a combination of experimentation and mathematical modeling to capture the complex interplay between cyclic loading, material microstructure, and fatigue damage. The criterion's effectiveness is validated through a series of fatigue tests on representative materials, demonstrating its superior predictive capability compared to conventional methods. This research offers a new paradigm for fatigue analysis, enabling more reliable design and performance assessment of critical components in various engineering applications.

Abstract: Buildings have become experimental grounds for architectural technology, sustainable practices, and human-centered design principles to be tested and refined. This paradigm shift has not only transformed the physical aspects of urban environments but has also redefined the relationship between architecture, end-users, and the built environment. Advancements in technology paved the way for a revolutionary approach to architecture, that involves responsiveness and adaptability to the environment, leading to the spread of the so-called Smart Architecture, buildings able to fit in with their ever-changing surroundings. Smart buildings present, in general terms, a global enhancement of their performance features, having the potential to impact the built environment in a new interacting, and engaging way, making architecture more accessible, performant, and user-friendly. This paper summarizes the results of a study aimed at identifying and classifying a sample of applications of advanced materials and technologies in the context of building envelopes, considered representative of relevant Smart Architecture solutions. The categorization will be done according to four categories: biomimicry, smart materials, kinetic elements, and 3D printed solutions. This results in a database of Smart Architecture case studies that collects brief details of each application and working principles, together with data regarding design practice, technology readiness, and economic aspects, among others.

Abstract: This research explores the development of advanced materials known as natural fiber reinforced polymer (FRP) composites with the aim of enhancing overall quality of life. Hybrid fibers derived from durian/luffa fibers were integrated into Polyethylene (PE) matrices to fabricate hybrid natural fiber PE composites. The study involves a comprehensive examination of these composites through tensile testing, scanning electron microscopy (SEM), and Fourier-Transform Infrared (FTIR) analysis. Results indicate that the tensile strength of the durian/luffa PE (DLPE) composite surpasses that of neat PE laminates, highlighting its superior stress tolerance. Overall, the composites exhibit specific tensile strength and modulus, contributing to the creation of lightweight materials compared to neat PE. SEM analysis indicates satisfactory fiber-to-matrix bonding with room for improvement, as observed gaps between fibers and matrix are present. FTIR analysis uncovers constituents in the chemical composition of durian and luffa fibers. The inclusion of natural fibers as an alternative to synthetic counterparts aligns with Sustainable Development Goals (SDG) standards. This research underscores the feasibility and benefits of fiber hybridization, emphasizing improved mechanical strength, environmental sustainability, and cost efficiency.

Abstract: Graphene has particularly interesting chemical and physical properties, including high chemical and mechanical resistance, excellent thermal and electric transport, high transparency. It combines the peculiarity of being an extremely light material with exceptional mechanical strength properties. Micro/nanoelectronics represents one of the key enabling technologies (KETs) of the future; it is the basis of innovation and competitiveness of almost all scientific and applicative sectors. Activities involving it are aimed at the development of new materials, processes, devices and technologies in a wide range of sectors, involving quantum information manipulation, multi-functional platforms, advanced materials, devices on flexible substrates. In the field of sensoristics, it is possible to create devices for applications in most sectors of global interest, such as punctual sensors, biosensors, specific transducers, multisensoristic systems, flexible sensoristic systems, multifunctional systems, advanced MEMS/MOEMS technologies for sensoristics, micro/nanoactuators, devices for energy convertion, gravimetric-electrochemical sensors. The paper provides an interesting overview of the possible applications of graphene in relation to its mechanical, thermal and optical properties, and relatively to the gas and biological sensoristic aspects, so as interesting informations for the increase in nanobio-devices performance by last efforts in theoretical nanophysics.

Abstract: Some recent trends and developments in advanced manufacturing of advanced materials from macro-to nanoscale subjected to shock loading, i.e. the up-to-date very important engineering area from industrial, research and academic points of view, with industrial applications to net-shape manufacturing, bioengineering, energy and safety, an outcome of the very extensive, over 40 years, work on this field performed by the author and his research international team, are briefly outlined.

Abstract: A general overview on the processing of a series of advanced engineering materials, synthesized via pulsed-electric-current-sintering related techniques, and the similarities in between those techniques are introduced in this work. This paper is focused on two major techniques; namely, the Spark Plasma Extrusion (SPE) and Current Assisted Infiltration Sintering (CAIS), which in turn are derived from the Spark Plasma Sintering (SPS) technique, all widely used by this research group. Not only the geometry but also the microstructure of thus prepared specimens might vary depending on the selected technique. The resulting specimens can be under the forms of discs (flat or thick coin-like), rivets (enlarged cylindrical bars)-like and/or disclosing interpenetrated periodic networks with regular or irregular (either coin or rivet/screw)-like specimens, respectively. As for the CAIS technique, either 3D printed ceramic frameworks or naturally synthesized porous substrates (such as bone-like structures), can be infiltrated with virtually any metal or alloy. Among the series of produced materials we can include, for example: biomaterials such as: Ti-and Mg-hydroxyapatite, pure hydroxyapatite HA, composites, e.g., Al5083-CNT ́s, just to name a few. The expanding possibilities of SPS, SPE and CAIS techniques are briefly indicated here.

Abstract: Soda lakes located close to uranium deposits of West Mongolia contain elevated concentrations of uranium, reaching, in some cases, 1 to 3 mg/l. The concentration of uranium in the lakes of Russian Altai is lower and varies from 0.001 to 0.03 mg/l. The greatest uranium resources (about 6000 tons) are stored in Hyargas Nuur Lake, Western Mongolia. In addition to uranium and salts of sodium and magnesium increased contents of boron (up to 250 mg/l), bromine (up to 1.1 g/l), lithium (up to 600 mg/l), strontium (up to 8 mg/l) were determined in the lake waters. A scheme for complex processing of uranium-bearing lake waters, the first stage of which includes extraction of uranium using iron-containing sorbents or anion exchange resins is considered. Uranium compounds, bromine, iodine, boron, lithium and other elements found in salt lakes are an important raw material base for the production of advanced materials.

Abstract: Additive Manufacturing using laser deposition has a great deal of attractiveness as a fabrication technique for metals and alloys. The combination of a high heat input, small molten volume, and incremental addition also is well suited for the production of high performance alloys and composites. The high cooling rates inherent in the process produces refined microstructures, leading to excellent as-deposited mechanical properties in conventional alloys. The high heating rates and cooling rates potentially lends itself to structurally amorphous alloys, functionally gradient materials, and nanostructured materials, among other more exotic metallic materials. By monitoring the process a map of the quality of the build can be recorded for quality assurance and validation. Flaws detected during fabrication can then be repaired in-situ. Realizing this potential will require a combination of modeling, experimental validation, and new design paradigms. Together this will lead to the greatest properties and functionalities in future products.

Abstract: In this paper, some recent developments in materials applied in sheet metal forming processes will be overviewed mainly from the viewpoint of automotive industry as one of the most important application fields. If we consider the main requirements in the automotive industry we can state that there are very contradictory demands on developments. Better performance with lower consumption and lower harmful emission, more safety and comfort are hardly available simultaneously with conventional materials and conventional manufacturing processes. These requirements are the main driving forces behind the material and technological developments in sheet metal forming: application of high strength steels, low weight light alloys and the appropriate non-conventional forming processes are the main target fields of developments summarized in this paper.