The lack of specific standards for characterization of materials manufactured by Fused Deposition Modelling (FDM) makes the assessment of the applicability of the test methods available and the analysis of their limitations necessary; depending on the definition of the most appropriate specimens on the kind of part we want to produce or the purpose of the data we want to obtain from the tests. In this work, the Spanish standard UNE 116005:2012 and international standard ASTM D638–14:2014 have been used to characterize mechanically FDM samples with solid infill considering two build orientations. Tests performed according to the specific standard for additive manufacturing UNE 116005:2012 present a much better repeatability than the ones according to the general test standard ASTM D638–14, which makes the standard UNE more appropriate for comparison of different materials. Orientation on-edge provides higher strength to the parts obtained by FDM, which is coherent with the arrangement of the filaments in each layer for each orientation. Comparison with non-solid specimens shows that the increase of strength due to the infill is not in the same proportion to the percentage of infill. The values of strain to break for the samples with solid infill presents a much higher deformation before fracture.
Equal channel angular extrusion or pressing (ECAE or ECAP) is a process used in order to impart severe plastic deformations to processed materials with the aim of improving their mechanical properties by reducing the grain size. The grain size reduction leads to mechanical properties improvement. In the present study, a new die configuration is proposed for the ECAE process. The advantage of this die geometry is that it allows us to obtain higher plastic strain in each ECAE passage than traditional ECAE dies. It is important to optimize the die geometry, as the main aim of the ECAE process is to impart severe plastic deformations to the processed materials. Consequently, the higher the deformation, the better the improvement on the mechanical properties of the processed materials. In order to determine how variations on geometry affect the plastic strain of the processed materials finite element modeling (FEM) is used. Both analytical and FEM methods will allow us to affirm that by using this new die configuration it is possible to achieve higher deformation values per ECAE passage.
When there is a social consensus that industrial assets are in fact heritage elements of cultural interest, their conservation and reuse must be considered with approaches that offer greater guarantees and that prevent their exposure to aggressive actions. In order for this to materialise, many aspects must be included in the decision-making process, from the characteristics of an asset and its surroundings, to the valuable aspects that distinguish it and that must be protected. This study aims to develop tools that guide the decision-making process regarding the most appropriate activity for each specific case study. Multicriteria Decision Support Techniques are evaluated as adequate support to create a proposal that fulfils these objectives. Furthermore, the Analytic Hierarchy Process is adapted to develop methodologies for assessing both the heritage value and the most compatible uses according to the characteristics of the asset. Subsequently, they are connected and such considerations regarding the heritage value of the asset are incorporated into the final decision. The tools developed are then applied to a case study to test their performance, assess their usefulness, and identify possible applications and future developments.
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