Dpto. Ingeniería - Ingeniaritza Saila [desde mayo 2018 / 2018ko maiatzetik]

Permanent URI for this community

http://hdl.handle.net/2454/29219

Véase además departamentos anteriores a mayo 2018 / Ikus, halaber, 2018ko maiatza baino lehenagoko sailak

Dpto. Automática y Computación - Automatika eta Konputazioa Saila

Dpto. Ingeniería Mecánica, Energética y de Materiales - Mekanika, Energetika eta Materialen Ingeniaritza Saila

Dpto. Proyectos e Ingeniería Rural - Landa Ingeniaritza eta Proiektuak Saila

Browse

Now showing 1 - 12 of 12

Open Access
Advanced welding automation: Intelligent systems for multipass welding in Butt Double V-Groove and Tee Double Bevel configurations
(Elsevier, 2024-12-01) Curiel Braco, David; Suárez, Alfredo; Veiga Suárez, Fernando; Aldalur, Eider; Villanueva Roldán, Pedro; Ingeniería; Ingeniaritza
The paper addresses the imperative shift towards automation in welding processes, leveraging advanced technologies such as industrial robotic systems. Focusing on the reconstruction and classification of weld joints, it introduces a methodology for automatic trajectory determination. Utilizing a laser profilometer mounted on the robot, weld joints are reconstructed in three di- mensions, and spurious data is filtered out through signal processing. A classification algorithm, integrating signal processing and artificial intelligence, accurately categorizes joint profiles, in- cluding V-joints and single bevel T-joints. The proposed intelligent and adaptive system enhances welding automation by analyzing point cloud data from laser scanning to optimize welding tra- jectories. This study establishes a foundational framework for further refinement and broader application in welding automation. Key Points - Introduction of a methodology for automated trajectory determination in welding processes. - Utilization of laser scanning and signal processing for reconstruction and classification of weld joints. - Implementation of an intelligent and adaptive system to optimize welding trajectories
Open Access
Automatic trajectory determination in automated robotic welding considering weld joint symmetry
(MDPI, 2023) Curiel Braco, David; Veiga Suárez, Fernando; Suárez, Alfredo; Villanueva Roldán, Pedro; Aldalur, Eider; Ingeniería; Ingeniaritza
The field of inspection for welded structures is currently in a state of rapid transformation driven by a convergence of global technological, regulatory, and economic factors. This evolution is propelled by several key drivers, including the introduction of novel materials and welding processes, continuous advancements in inspection technologies, innovative approaches to weld acceptance code philosophy and certification procedures, growing demands for cost-effectiveness and production quality, and the imperative to extend the lifespan of aging structures. Foremost among the challenges faced by producers today is the imperative to meet customer demands, which entails addressing both their explicit and implicit needs. Furthermore, the integration of emerging materials and technologies necessitates the exploration of fresh solutions. These solutions aim to enhance inspection process efficiency while providing precise quantitative insights into defect identification and location. To this end, our project proposes cutting-edge technologies, some of which have yet to gain approval within the sector. Noteworthy among these innovations is the integration of vision systems into welding robots, among other solutions. This paper introduces a groundbreaking algorithm for tool path selection, leveraging profile scanning and the concept of joint symmetry. The application of symmetry principles for trajectory determination represents a pioneering approach within this expansive field.
Open Access
Effect of the heat input on wire-arc additive manufacturing of invar 36 alloy: microstructure and mechanical properties
(Springer, 2022) Veiga Suárez, Fernando; Suárez, Alfredo; Artaza, Teresa; Aldalur, Eider; Ingeniería; Ingeniaritza; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Invar, also known as FeNi36, is a material of great interest due to its unique properties, which makes it an excellent alternative for sectors such as tooling in aeronautics and aerospace. Its manufacture by means of wire arc additive manufacturing (WAAM) technology could extend its use. This paper aims to evaluate the comparison of two of the most widespread WAAM technologies: plasma arc welding (PAW) and gas metal arc welding (GMAW). This comparison is based on the analysis of wall geometry, metallography, and mechanical properties of the material produced by both technologies. The results show a slight increase in toughness and elongation before fracture and worse tensile strength data in the case of PAW, with average values of 485 MPa for ultimate tensile strength (UTS), 31% for elongation and 475 MPa, 40% in GMAW and PAW, respectively. All results gathered from the analysis show the possibility of successful manufacturing of Invar by means of WAAM technologies. The novelties presented in this paper allow us to establish relationships between the thermal input of the process itself and the mechanical and metallographic properties of the material produced.
Open Access
Effect of the metal transfer mode on the symmetry of bead geometry in WAAM aluminum
(MDPI, 2021) Veiga Suárez, Fernando; Suárez, Alfredo; Aldalur, Eider; Bhujangrao, Trunal; Ingeniería; Ingeniaritza
The symmetrical nature in the case of wall fabrication by wire arc additive manufacturing (WAAM) has been observed in the literature, but it has not been studied as a source of knowledge. This paper focuses on the comparative study of three drop transfer methods employing Gas Metal Arc Welding (GMAW) technology, one of the most reported for the manufacture of aluminum alloys. The transfer modes studied are the well-known pulsed GMAW, cold arc, and the newer pulsed AC. The novelty of the last transfer mode is the reversal of the polarity during the preparation phase of the substance for droplet deposition. This study compares the symmetry of zero beads to deter-mine the best parameters and transfer modes for wire arc additive manufacturing of 5 series aluminum. The pulsed transfer modes show values of 0.6 for symmetry ratio, which makes them more interesting strategies than cold arc with a symmetry ratio of 0.5. Furthermore, the methodology proposed in this study can be extrapolated to other materials manufactured with this technology.
Open Access
Intelligent and adaptive system for welding process automation in T-shaped joints
(MDPI, 2023) Aldalur, Eider; Suárez, Alfredo; Curiel Braco, David; Veiga Suárez, Fernando; Villanueva Roldán, Pedro; Ingeniería; Ingeniaritza
The automation of welding processes requires the use of automated systems and equipment, in many cases industrial robotic systems, to carry out welding processes that previously required human intervention. Automation in the industry offers numerous advantages, such as increased efficiency and productivity, cost reduction, improved product quality, increased flexibility and safety, and greater adaptability of companies to market changes. The field of welding automation is currently undergoing a period of profound change due to a combination of technological, regulatory, and economic factors worldwide. Nowadays, the most relevant aspect of the welding industry is meeting customer requirements by satisfying their needs. To achieve this, the automation of the welding process through sensors and control algorithms ensures the quality of the parts and prevents errors, such as porosity, unfused areas, deformations, and excessive heat. This paper proposes an intelligent and adaptive system based on the measurement of welding joints using laser scanning and the subsequent analysis of the obtained point cloud to adapt welding trajectories. This study focuses on the optimization of T-joints under specific welding conditions and is intended as an initial implementation of the algorithm, thus establishing a basis to be worked on further for a broader welding application.
Open Access
Symmetry analysis in wire arc direct energy deposition for overlapping and oscillatory strategies in mild steel
(MDPI, 2023) Uralde Jiménez, Virginia; Veiga Suárez, Fernando; Suárez, Alfredo; Aldalur, Eider; Ballesteros Egüés, Tomás; Ingeniería; Ingeniaritza
The field of additive manufacturing has experienced a surge in popularity over recent decades, particularly as a viable alternative to traditional metal part production. Directed energy deposition (DED) is one of the most promising additive technologies, characterized by its high deposition rate, with wire arc additive manufacturing (WAAM) being a prominent example. Despite its advantages, DED is known to produce parts with suboptimal surface quality and geometric accuracy, which has been a major obstacle to its widespread adoption. This is due, in part, to a lack of understanding of the complex geometries produced by the additive layer. To address this challenge, researchers have focused on characterizing the geometry of the additive layer, particularly the outer part of the bead. This paper specifically investigates the geometrical characteristics and symmetry of walls produced by comparing two different techniques: an oscillated strategy and overlapping beads.
Open Access
Symmetry and its application in metal additive manufacturing (MAM)
(MDPI, 2022) Uralde Jiménez, Virginia; Veiga Suárez, Fernando; Aldalur, Eider; Suárez, Alfredo; Ballesteros Egüés, Tomás; Ingeniería; Ingeniaritza
Additive manufacturing (AM) is proving to be a promising new and economical technique for the manufacture of metal parts. This technique basically consists of depositing material in a more or less precise way until a solid is built. This stage of material deposition allows the acquisition of a part with a quasi-final geometry (considered a Near Net Shape process) with a very high raw material utilization rate. There is a wide variety of different manufacturing techniques for the production of components in metallic materials. Although significant research work has been carried out in recent years, resulting in the wide dissemination of results and presentation of reviews on the subject, this paper seeks to cover the applications of symmetry, and its techniques and principles, to the additive manufacturing of metals.
Open Access
Thermal expansion behaviour of Invar 36 alloy parts fabricated by wire-arc additive manufacturing
(Elsevier, 2022) Aldalur, Eider; Suárez, Alfredo; Veiga Suárez, Fernando; Ingeniería; Ingeniaritza
Invar 36 alloy is of high interest in various industrial sectors, due to its reduced thermal expansion properties. This study aims to validate Wire-Arc Additive Manufacturing (WAAM) technology as a valid method for manufacturing aerospace tooling in Invar 36. The main novelty and the objective of this work is to study the properties of Invar deposited by WAAM technology and to provide guidelines for the manufacture of parts using this technology. To do so, the thermal expansion behaviour of Invar specimens manufactured using Gas Metal Arc Welding (GMAW)-based WAAM technology and Plasma Arc Welding (PAW)-based WAAM technology is analyzed for subsequent comparison with the values obtained from the laminated Invar sample used as the reference specimen. A wall is manufactured with each technology, for comparative purposes, from which specimens were extracted for the dilatometry test and metallographic analysis. The results of these analyses show the advantages of GMAW technology for the manufacture of Invar alloy parts, as it presents the same thermal expansion behaviour as the laminated reference material with less presence of precipitates and no macrostructural failures such as pores, cracks and lacks of fusion. Furthermore, to conclude, an aeronautical tooling that has been manufactured within this work demonstrated the potential of this technology to manu-facture specialized aeronautical parts.
Open Access
Tomography analysis of Al-Mg alloys manufactured by wire-arc directed energy deposition with different metal transfer modes
(Elsevier, 2023) Aldalur, Eider; Suárez, Alfredo; Veiga Suárez, Fernando; Holgado, Ibon; Ortega, Naiara; Ingeniería; Ingeniaritza
The interest in aluminum-magnesium alloy additive manufacturing through Wire-arc Directed Energy Deposition (DED) technology has substantially grown in recent years. The main challenge in additive manufactured aluminum-magnesium alloys is the occurrence of porosity. In this context, Gas Metal Arc Welding (GMAW) based additive technology is suitable for aluminum printing as it allows high deposition rates and reduces porosity levels through alternative metal transfer modes without adding any extra equipment. Therefore, this research explores the effects of these alternative metal transfer modes, which determine the current signal shape and polarity, on the distribution and morphology of micropores using X-ray computed tomography in both single-bead and double-bead walls. The novelty of this paper lies in the comparison of the porosity obtained using alternative transfer modes, which, unlike CMT (Cold Metal Transfer) modes, have not been exhaustively analyzed. Additionally, to date, there has been no comprehensive comparison of the porosity results obtained in single walls and overlapped walls. The results demonstrate that pulsed-AC transfer mode with a current signal featuring variable polarity yields acceptable porosity fraction values of less than 0.04% in single-bead walls and less than 0.01% in double-bead walls, achieving high productivity.
Open Access
Validation of the mechanical behavior of an aeronautical fixing turret produced by a design for additive manufacturing (DfAM)
(MDPI, 2022) Veiga Suárez, Fernando; Bhujangrao, Trunal; Suárez, Alfredo; Aldalur, Eider; Goenaga, Igor; Gil Hernández, Daniel; Ingeniería; Ingeniaritza
The design of parts in such critical sectors as the manufacturing of aeronautical parts is awaiting a paradigm shift due to the introduction of additive manufacturing technologies. The manufacture of parts designed by means of the design-oriented additive manufacturing methodology (DfAM) has acquired great relevance in recent years. One of the major gaps in the application of these technologies is the lack of studies on the mechanical behavior of parts manufactured using this methodology. This paper focuses on the manufacture of a turret for the clamping of parts for the aeronautical industry. The design of the lightened turret by means of geometry optimization, the manufacture of the turret in polylactic acid (PLA) and 5XXX series aluminum alloy by means of Wire Arc Additive Manufacturing (WAAM) technology and the analysis by means of finite element analysis (FEA) with its validation by means of a tensile test are presented. The behavior of the part manufactured with both materials is compared. The conclusion allows to establish which are the limitations of the part manufactured in PLA for its orientation to the final application, whose advantages are its lower weight and cost. This paper is novel as it presents a holistic view that covers the process in an integrated way from the design and manufacture to the behaviour of the component in use.
Open Access
Wall fabrication by direct energy deposition (DED) combining mild steel (ER70) and stainless steel (SS 316L): microstructure and mechanical properties
(MDPI, 2022) Uralde Jiménez, Virginia; Suárez, Alfredo; Aldalur, Eider; Veiga Suárez, Fernando; Ballesteros Egüés, Tomás; Ingeniería; Ingeniaritza
Direct energy deposition is gaining much visibility in research as one of the most adaptable additive manufacturing technologies for industry due to its ease of application and high deposition rates. The possibility of combining these materials to obtain parts with variable mechanical properties is an important task to be studied. The combination of two types of steel, mild steel ER70-6 and stainless steel SS 316L, for the fabrication of a wall by direct energy deposition was studied for this paper. The separate fabrication of these two materials was studied for the microstructurally flawless fabrication of bimetallic walls. As a result of the application of superimposed and overlapped strategies, two walls were fabricated and the microstructure, mechanical properties and hardness of the resulting walls are analyzed. The walls obtained with both strategies present dissimilar regions; the hardness where the most present material is ER70-6 is around 380 HV, and for SS 316L, it is around 180 HV. The average values of ultimate tensile strength (UTS) are 869 and 628 MPa, yield strength (YS) are 584 and 389 MPa and elongation at break are 20% and 36%, respectively, in the cases where we have more ER70-6 in the sample than SS 316L. This indicates an important relationship between the distribution of the materials and their mechanical behavior.
Open Access
Weld joint reconstruction and classification algorithm for trajectory generation in robotic welding
(Trans Tech Publications, 2023) Curiel Braco, David; Veiga Suárez, Fernando; Suárez, Alfredo; Villanueva Roldán, Pedro; Aldalur, Eider; Ingeniería; Ingeniaritza

Browse

Browsing Dpto. Ingeniería - Ingeniaritza Saila [desde mayo 2018 / 2018ko maiatzetik] by Author "Aldalur, Eider"

Results Per Page

Sort Options