 On October 10th, Sérgio Tavares was the first student from FEUP (Faculdade de Engenharia da Universidade do Porto) to be graduated under the MIT Portugal Program. Sérgio started his PhD in 2007 and since then he has been developing his thesis on “Design and Advanced Manufacturing of Aircraft Structures using Friction Stir Welding”. His project aimed to contribute to the development of the Portuguese aeronautical industry and included the development of new approaches in aeronautic manufacturing, where a new joining process was used as case study.
Sérgio did his PhD under supervision of Paulo de Castro (FEUP), Pedro Vilaça (IST), Thomas Eagar (MIT), J. dos Santos (HZG, Germany) and M. Pachione (Airbus, Germany). During his PhD, Sérgio has submitted two patents and has published eight papers in international journals and has presented his work at several international conferences. 1) What is your hometown? My hometown is Oliveira de Azeméis, a small city between Aveiro and Porto in an industrialized area which has been a Portuguese hub for injection molds and metallurgic industry, which influenced my background. 2) How did you learn about the MIT Portugal Program and what motivated you to apply for the EDAM PhD? I knew this program in its early stages from a presentation of a pilot project between MIT Portugal and Volkswagen Autoeuropa. At that time, I was finishing my master degree and I was decided to do a PhD. When I collected information about these new PhD programs, the description for EDAM area and for LTI program arouse my interest due to its multidisciplinary approach for research and the strong link with industries. The curriculum part was an additional motivation, due to the product development courses and the management topics related to the production systems. 3) What was your research project about and what did you achieved? The project in which I was involved is related to the application of a new joining process to improve the structural efficiency of large aircrafts. Aeronautical transportation, as all other transportation sectors, has a huge demand for the reduction of pollutant emissions and operational costs, and at the same time, for increasing aircraft dispatch reliability and comfort of the passengers, which puts more pressure on the development of new design solutions and concepts in the complete system including the structure. This project analyzed the application of friction stir welding in a multi-perspective framework taking into account the requirements and drivers in new product and process development in aeronautics. Aeronautical structures continue to use extensively riveting as the joining processes for their structural parts. However, from an efficiency and lean point of view, these joints can be much more simple and lighter. For instance, if the joints are simply butt joined it is possible to eliminate thousands of fasteners, overlap areas and sealants which are applied in most aircraft joints. The replacement of these riveted joints by other advanced manufacturing technologies, as friction stir welding, can bring significant weight and cost savings with a simplified design of the airframe, leading to Leaner manufacturing processes. 4) What are the major benefits of this project on peoples’ lives? Since more efficient and environmentally friendly transportation systems require increasingly lighter structures, any step in this direction has huge impact in the reduction of emissions due to the great life-cycle, which in some cases can be more than 40 years. The process investigated improves simultaneously the structural efficiency and the production costs, giving benefits to the different stakeholders of this sector. Direct benefits from this project are related to the new concepts that were developed and investigated that can be applied by Portuguese industry in this area. In addition, the comprehensive approach considering multidisciplinary aspects related to the process infusion in complex systems used along this research can improve the adoption of new technologies reducing its risk in safety critical systems. 5) How do you see this area evolving in the future? The aeronautical sector is highly focused in cost and weight reduction. The first approach by the major aeronautical manufacturers has been the adoption of new materials in aeronautical primary structures which can lead to higher structural efficiency in terms of weight and cost reduction. However, materials and manufacturing costs are increasing with this tendency. Therefore, different approaches in the future will be taken into account, considering not only new materials but also new structural concepts and new manufacturing processes. Additionally, new hybrid structural solutions will be adopted in order to take advantage of the different properties of the different materials suitable for this kind of structures. This methodology will lead to more complex solutions but the structural efficiency and passenger comfort will be improved. 6) How do you think this kind of research project/ international partnership can positively contribute for Portugal’s economic development? Aeronautical industry has a significant impact in the Portuguese economy. An important fact, that is almost unknown among us, is that the aircraft manufacturing and maintenance Portuguese industry is among the top ten in Europe, employing directly more than 5,000 high skilled people only in manufacturing and maintenance. During this project, it was possible to involve the biggest Portuguese companies related to this field, OGMA and TAP Maintenance and Engineering, the research laboratory HZG, in Germany, with large experience in the friction stir welding process and Airbus, the biggest aircraft manufacturer in Europe, through an internship in two departments that are investigating this process for future aircraft. A stay of 6 months at MIT also positively contributed for the final result due to their experience in different approaches to deal with complex systems and their development. In addition, it was possible to interact with high tech companies in the vicinity of MIT, leaders in different technologies which can be used to improve the application of this manufacturing process. These different exchanges contributed to improve the approaches applied in the Portuguese companies for new process implementation and enhanced the relations with institutions of reference in research and manufacturing. 7) Now that you have finished your PhD, what are your plans? And in which was this influenced/ determined by your PhD at FEUP under the MIT Portugal Program? Now I’m still doing some additional research in areas related to my thesis and gaining teaching experience in mechanical engineering and product development topics. I also started to do entrepreneurial activities related to the environment. This PhD gave me the possibility to think in the problems in a more holistic and structured way, improving my skills in the management of process and product development. It also contributed for a better perception on how to make compatible the research of new solutions done in laboratory and the research and development required for industrial or commercial purposes, giving opportunity to improve the synergies between industries, research centers and universities in Portugal. 
| 
