Recent work has shown that it is possible to obtain ODS (Oxide Dispersion Strengthened) austenitic steels for use under intense flux. These new grades are beginning to be studied for nuclear applications around the world. They should have remarkable properties, particularly in terms of resistance to swelling under irradiation and creep, thanks to the addition of nano-reinforcements in exceptional density (10^23 to 10^24 m-3). These ODS steels are obtained by powder metallurgy, by co-grinding a metal powder with an oxide powder. The aim of this work is to succeed in manufacturing, using an innovative process, ODS austenitic steel cladding tubes. It will be necessary to master the recrystallization of these tubes, to propose a first critical evaluation by specifying the property/microstructure relationships and by evaluating, by irradiation with charged particles, the behavior under irradaition of this new material. The student will be trained in Scanning Electron Microscopy and the techniques that result from it (X-ray analysis, EBSD, etc.), in SAXS, in the performance and exploitation of mechanical tests. He will have to acquire good notions in Transmission Electron Microscopy and in Tomographic Atomic Probe. The understanding of the behavior under irradiation will be guided by simulations by cluster dynamics.