Development of laser welding processes between copper alloy and Cr-Mo steels for the realization of nuclear fusion machines’ cooling systems.

This project of thesis has the main purpose to investigate the dissimilar welds between CuCrZr alloy and EUROFER, as a little activity in the EUROFUSION program context. EUROFUSION is a very ambitious program, aiming at providing mankind with clean, stable and virtually infinite energy through the use of controlled thermo-nuclear fusion reaction. The EUROFUSION program is based on the roadmap to the realisation of fusion energy. The program has two main pillars: preparing for ITER experiment and developing a concept for the future demonstration fusion power plant DEMO. This very important goal will be reached, based on the previsions, by 2050 with the starting of the operations of DEMO, the first nuclear fusion reactor able to produce energy in a safe, clean and economically convenient way. In order to achieve this goal, over 4800 researchers from more than 30 member institutes and more than 150 research entities are involved. For this reason, EUROFUSION program can be considered one of the most important, challenging and fascinating bets in science history; the accomplishment of such a project could completely change our lives and our way to produce energy, while giving mankind a sustainable alternative to carbon dioxide intensive energy sources and it could completely redefine the energy production sector. Therefore, as already said, many national and international agencies from all over Europe are committed to achieve this goal as fast as possible, among these we find ENEA, the Italian National Agency for New Technologies, Energy and Sustainable Economic Development. ENEA, among other tasks, is committed to finding innovative solutions from the material research point of view; in particular, during this project of thesis, research activity carried out about dissimilar laser welding between CuCrZr and P91 steel for application in the DEMO project will be discussed, highlighting the great potential of this technology and its possible application in fusion field, as well as the limitations and drawbacks and possible strategies to cope with them.