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Los principales objetivos de este trabajo son:  Evaluar el conocimiento previo: determinar de manera sistemática cuánto saben los estudiantes antes de cada clase sobre los temas específicos de la asignatura donde se aplica.  Personalizar la enseñanza: ajustar el contenido y el enfoque de las clases según los resultados de los cuestionarios previos, de modo que se adapte a las necesidades individuales de los estudiantes.  Incentivar la participación activa: estimular la participación activa de los estudiantes al utilizar los cuestionarios previos como punto de partida para debates y actividades de aprendizaje en el aula. Fomentar la autorregulación: ayudar a los estudiantes a desarrollar habilidades de autorregulación al requerir que evalúen y gestionen su propio aprendizaje antes de las sesiones. 3. METODOLOGÍA Esta propuesta se aplica en la asignatura Procesos de Fabricación que se imparte en el tercer curso del grado en Ingeniería Electrónica Industrial Esta asignatura pertenece a la rama técnica de los grados en ingeniería y su temario es extenso. Esta asignatura se basa en conocimientos previos del área de conocimiento de ciencia e ingeniería de los materiales, asignatura del segundo curso del grado. La metodología de implementación de cuestionarios anteriores y posteriores en la asignatura es un enfoque pedagógico integral que se centra en la participación activa de los estudiantes y la adaptación continua de la enseñanza. Dado el elevado número de temas que presenta esta asignatura, los cuestionarios se realizan en aquellos principales, para poder cumplir la programación docente. La figura 1 indica los tres puntos fundamentales en los que se basa la metodología: 1. Diseño de cuestionarios, 2. Análisis de los resultados y 3. Seguimiento de resultados.

This research work presents an experimental investigation on the formability and failure of additively manu- factured polymer sheets. To this regard, Nakajima formability tests following different principal strain paths have been conducted on 2 selected FDM-printed polymer sheet materials, polyethylene terephthalate glycol and polycraprolactone, this being carried out for the first time ever, as far as the plastic behavior and formability study of this kind of 3D printed materials has been limited so far uniquely to conventional tension or compression tests. The analysis includes the evaluation of the different types of failure under plastic deformation for each material considered, allowing the assessment of the overall formability limits within the materials forming limit diagrams combined with the failure evaluation performed via optical microscopy. Thus, the results provided the overall characterization in terms of sheet formability and the comprehensive assessment of the different failure modes and the forming conditions upon which each type of failure is attained for each of the two printed ma- terials. Furthermore, these results allow the authors to create an essential evaluation framework for the ongoing research on process hybridization including the combination of 3D printing technologies with innovative forming processes such as incremental sheet forming.

The flanging of metal sheets is extensively used in the automotive and aeronautical industries to provide rigidity or support for subsequent assembly. Flanging by rubber pad forming is one of the most common processes for small and medium batch production. Flanges with nonlinear bending lines are exposed to severe conditions that significantly hinder our comprehension of the geometrical, material, and process factors associated with flange formability (i.e., flangeability). This work presents a numerical study of the flanging process by a tailored rubber pad of hollow AA7075-O parts with continuous concave and convex flanges. The flangeability limits, the geometric capabilities of the forming process, and the deformation mechanisms of stretched and shrunk flanges as well as in the transition zone between them are analysed.

Durante las últimas décadas, el paradigma de la Industria 4.0, que se dirige hacía procesos flexibles, de baja-media producción, y orientados hacía la personalización del producto, ha provocado grandes cambios en los procesos de fabricación, ejemplo de esta evolución es el avance que ha tenido la fabricación aditiva en los últimos años. Otro claro ejemplo de esta evolución se ha visto en el proceso denominado conformado incremental mono-punto o SPIF (por sus siglas en inglés), que permite gran flexibilidad de proceso, ahorro de utillaje y permite la fabricación de productos customizados. Recientemente, la aplicación de SPIF a materiales poliméricos se ha visto incrementada, debido a que además de las ventajas del proceso mencionadas anteriormente, se han realizado verificaciones experimentales de que las deformaciones alcanzadas mediante SPIF se encuentran por encima de la curva límite de conformado por estricción o FLC (por sus siglas en inglés), sin fallo. Sin embargo, cabe señalar que en el caso de las láminas poliméricas no existe un procedimiento sistemático para construir el diagrama límite de conformado o FLD como está bien definido para chapa metálica. En este contexto, la primera parte de esta tesis doctoral tiene el objetivo de proporcionar procedimientos para obtener la curva límite de conformado por estricción (FLC por sus siglas en inglés) y por fractura en modo I de mecánica de fractura (FFL por su siglas en inglés), y con ello, obtener el diagrama límite de conformado (FLD) de materiales poliméricos. Las láminas poliméricas escogidas fueron tres polímeros termoplásticos ampliamente utilizados: policarbonato (PC por sus siglas en inglés), polietileno de alto peso molecular (UHMWPE por sus siglas en inglés) y polieteretercetona (PEEK por sus siglas en inglés). Por otro lado, esta tesis doctoral establece un marco de estudio de distintos parámetros de proceso en SPIF, con el objetivo de asentar una base experimental sobre la afectabilidad de estos paráme

In industries as diverse as automotive, aerospace, medical, energy, construction, electronics, and food, the engineering technology known as 3D printing or additive manufacturing facilitates the fabrication of rapid prototypes and the delivery of customized parts. This article explores recent advancements and emerging trends in 3D printing from a novel multidisciplinary perspective. It also provides a clear overview of the various 3D printing techniques used for producing parts and components in three dimensions. The application of these techniques in bioprinting and an up-to-date comprehensive review of their positive and negative aspects are covered, as well as the variety of materials used, with an emphasis on composites, hybrids, and smart materials. This article also provides an updated overview of 4D bioprinting technology, including biomaterial functions, bioprinting materials, and a targeted approach to various tissue engineering and regenerative medicine (TERM) applications. As a foundation for anticipated developments for TERM applications that could be useful for their successful usage in clinical settings, this article also examines present challenges and obstacles in 4D bioprinting technology. Finally, the article also outlines future regulations that will assist researchers in the manufacture of complex products and in the exploration of potential solutions to technological issues.

Single Point Incremental Forming (SPIF) is a dieless and flexible forming technology that allows performing complex shapes and presents a high economic payoff for low production series. In this context, this research presents an experimental investigation of Polyether ether ketone (PEEK) sheets deformed by SPIF at room temperature, determining the influence of the process parameters on the material formability. The research is performed in terms of principal strains that are evaluated within the material Forming Limit Diagram (FLD) obtained by means of Nakajima tests allowing to establish the forming limits of PEEK sheet material. On the other hand, the results of the SPIF tests performed gave rise to an analysis in terms of formability, modes of failure, temperature, forming force, and geometry accuracy. These experiments allow assessing the optimal parameters and forming methodologies/procedures for the manufacturing of cranio-maxillofacial prostheses. In this sense, it was performed a global study in terms of the formability of the manufactured prostheses, as well as the shape accuracy, temperature and roughness analysis, among others. This research showed that the maximum strains attainable by the two prostheses were still found far away from the Fracture Forming Limit (FFL) of the material, showing the feasibility to obtain extra formability within the forming safe zone. In conclusion, this work proved the high potential of manufacturing prostheses in the biomedical field using Incremental Sheet Forming (ISF) processes in combination with advanced biocompatible polymers such as PEEK.

This work presents a comprehensive investigation of an experimental study conducted on ultra-high molecular weight polyethylene (UHMWPE) sheets using single point incremental forming (SPIF). The analysis is performed within a previously established research framework to evaluate formability and failure characteristics, including necking and fracture, in both conventional Nakajima tests and incremental sheet forming specimens. The experimental design of the SPIF tests incorporates process parameters such as spindle speed and step down to assess their impact on the formability of the material and the corresponding failure modes. The results indicate that a higher step down value has a positive effect on formability in the SPIF context. The study has identified the tool trajectory in SPIF as the primary influencing factor in the twisting failure mode. Implementing a bidirectional tool trajectory effectively reduced instances of twisting. Additionally, this work explores a medical case study that examines the manufacturing of a polyethylene liner device for a total hip replacement. This investigation critically analyses the manufacturing of plastic liner using SPIF, focusing on its formability and the elastic recovery exhibited by the material.

This article presents an experimental research performed on a polycarbonate sheet deformed by single point incremental forming (SPIF). The analysis is implemented within the framework developed in previous research work for assessing formability and failure by necking and fracture of polymeric sheets in conventional and incremental sheet forming (ISF) processes. The experimental plan is taking into account a series of process parameters, including tool diameter, feed rate, spindle speed and step down. The results allow an evaluation of the influence of these parameters on the formability and their effect on the failure modes. In this regard, three modes of failure were observed: fracture, twisting and crazing. It was shown that most of the typical forming conditions in SPIF lead to failure by fracture in the absence of necking (crack opening in mode I), and all the test conditions presented a combination of twisting and fracture. Higher values of the step down increased the intensity of twisting whereas high values of spindle speed resulted in crazing. A scanning electron microscopy (SEM) evaluation was performed as well as an integral temperature analysis to provide a complete window for understanding the conditions upon which the different failure modes of this thermoplastic material are developed in SPIF.

This study presents a numerical analysis of the tube expansion process by conventional tube-end forming versus single point incremental forming (SPIF) using DEFORM. The work includes the assessment of the strain paths within the principal strain space of these processes with respect to the formability limits as well as their evaluation within the equivalent strain versus stress triaxiality space. The results obtained demonstrated that the mechanics of tube flaring process in conventional and incremental forming are substantially different. This analysis of formability in the light of the accumulated equivalent strain and the average stress triaxiality allowed a better understanding of the differences between both processes in terms of the fracture limit strains.

Incremental Sheet Forming (ISF) and Fused Deposition Modelling (FDM) of polymers have both an edge over conventional manufacturing by their ability to directly get complex structures without the need of a mold or a die. Obtaining biocompatible polymer blanks for ISF is not always as easy as it could be expected. Concerning nowadays FDM offers a good opportunity to print biocompatible polymer sheets as blanks to next be formed by ISF. Exploring the combination of FDM and ISF for two biodegradable polymers (Polylactic acid (PLA) and Polycaprolactone (PCL)) is the objective of this work. An analysis of the initial printed sheets in terms of thickness uniformity and surface roughness was carried out. Truncated cone shape with fixed slope angle geometries in a CNC machine were formed. The ISF process parameters modified were the traditional: step down, feed rate and spindle speed. As saved outputs there are: Forming Forces, Maximum Temperature, Surface Integrity, Surface Roughness and Shape Accuracy. After this first approach, a good feasibility process window was established for being used on prosthesis manufacturing of PCL. On the contrary, the feasibility window for PLA is limited because of its low formability. The first results of the combination of both additive manufacturing processes are interesting and deserve further studies to evaluate more in depth the behaviors and the forming mechanism of these materials.