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For repairing turbine blades or die and mold forms, additive manufacturing processes are commonly used to build-up new material to damaged sections. Afterwards, a subsequent re-contouring process such as 5-axis ball end milling is required to remove the excess material restoring the often complex original geometries. The process design of the re-contouring operation has to be done virtually, because the individuality of the repair cases prevents actual running-in processes. Hard-to-cut materials e.g. titanium or nickel alloys, parts prone to vibration and long tool holders complicate the repair even further. Thus, a fast and flexible material removal simulation is needed. The simulation has to predict suitable processes focusing shape deviations under consideration of process stability for arbitrary complex engagement conditions. In this paper, a dynamic multi-dexel based material removal simulation is presented, which is able to predict high-resolution surface topography and stable parameters for arbitrary processes such as 5-axis ball end milling. In contrast to other works, the simulation is able to simulate an unstable process using discrete cutting edges in real-time.

Circular economy (CE) has been promoted worldwide as a strategy to reduce material use and to increase the material use efficiency by closing material loops at the societal level. The core concept of CE is to improve the circularity of material use through turning materials at the end of their service life into resources for others, however, there is very little information about the role of manufacturing in achieving CE. Using the concepts of dynamic material flow analysis and stock dynamics, this paper proposes a methodological approach to help understand the role of manufacturing in achieving CE. A number of other strategies such as material efficiency in conjunction with CE are also tested using the case of global steel use to draw conclusions.

[EN] One of the ways to increase students' motivation and participation in the classroom is to propose a wide variety of resources and activities so that the teaching materials to be used are suitable for the largest possible number of students. Today's students have grown up in an environment where technological supports are part of their daily lives. For this reason, this work proposes the incorporation of Information and Communication Technologies (TIC) together with other quality materials as a medium for information on teaching content. The main objective of this methodology is that the proposed tools allow learning the subject in a more attractive and enjoyable way, as well as promoting communication between students and teachers. This model has been implemented within the Mathematics I classes of the Degree in Industrial Electronic and Automatic Engineering, both in theory and in classroom and computer practices., [ES] Una de las maneras de aumentar la motivación y la participación en las aulas por parte de los alumnos es el planteamiento de una gran variedad de recursos y actividades de forma que los materiales docentes a trabajar se adecuen al mayor número de alumnos posible. Los alumnos de hoy en día han crecido en un ámbito donde los soportes tecnológicos forman parte de su vida cotidiana. Por ello, en este trabajo se propone la incorporación de las Tecnologías de la Información y la Comunicación (TIC), junto con otros materiales de calidad obtenidos en la web, como soporte de información de los contenidos docentes. El objetivo principal es que las herramientas propuestas permitan profundizar en la materia de forma más atractiva y amena, así como fomentar la comunicación entre alumnos y profesores. Este modelo se ha implementado dentro de las clases de Matemáticas I del Grado en Ingeniería Electrónica Industrial y Automática, tanto en la teoría como en las prácticas de aula e informáticas.

Nearly all the traditional man-made materials are static in both form and function, and only quite recently the synthetic materials chemists have shifted their attention to the dynamic materials. These dynamic materials have multiple advantages over their static counterparts: selected properties of interest can be reversibly ‘‘turned on’’ and ‘‘off’’ at will and the ability to reconfigure these materials imparts upon them many uses.

In order to estimate the distribution, as well as the magnitude, of dynamic material pressures on ground-supported silos a simplified seismic analysis procedure was utilized. The seismic analysis of silos can be complex, as the evaluation of several parameters must be taken into consideration, including the properties of bulk materials used and how the bulk materials and silo wall are joined together. It is therefore useful to develop an analytical approximation in order to better assess results. In addition to a simplified model for the seismic analysis of a silo–bulk material system being utilized, a three-dimensional finite element model was also incorporated. Using the finite element method, a more realistic representation of the structure is possible. Moreover, the finite element method also takes into consideration contact problems between the bulk material and the silo wall, which results in easier analyses. Both a squat and a slender silo were selected for this study. The results obtained in the study of selected examples were compared with those findings obtained via EN1998-4. Modified Veletsos and Younan approximations, which are commonly used for the analysis of grain silos, were also used. Results and analysis concluded that the proposed analytical model provided, overall, a good outcome, especially in regards to the analysis of dynamic material pressure. It should be noted that using the analytical method as proposed in Eurocode, the dynamic material pressure for squat silos can be underestimated, but the results for slender silos are stronger.

A dual-coded dynamic material was created by the bimodal self-assembly protocol sketched in the scheme. The combination of two orthogonal and reversible interactions, namely solvophobic aggregation (SA) and metal coordination (MC), allows precise control at each step of the self-assembly cycle, leading to the formation of rodlike supramolecular architectures.

International audience; New dynamic materials, that can repair themselves after strong damage, have been designed by hybridization of polymers with structurally well-defined nanobuilding units. The controlled design of cross-linked poly(n-butyl acrylate) (pBuA) has been performed by introducing a very low amount of a specific tin oxo-cluster. Sacrificial domains with non-covalent interactions (i.e. ionic bonds) developed at the hybrid interface play a double role. Such interactions are strong enough to cross-link the polymer, which consequently exhibits rubber-like elasticity behavior and labile enough to enable, after severe mechanical damage, dynamic bond recombination leading to an efficient healing process at room temperature. In agreement with the nature of the reversible links at the hybrid interface, the healing process can speed up considerably with temperature. H-1 and Sn-119 PFG NMR has been used to evidence the dynamic nature of these peculiar cross-linking nodes.

International audience; This short conixibution aims at introducing the motion of dynamic materials as initiated by Blekhman and Lurie) and the corresponding allied techniques of homogenization and asymptotic analysis. Main role is played by the canonical conservation laws of energy and wave momentum - the latter most often ignored in the field of continumn mechanics - as follows from an application of the celebrated theorem of E. Noether