Effect of surface shot peening on the microstructure and mechanical properties of fuel cladding 1515-Ti austenitic steel

Lead-bismuth fast reactor is considered to be the most promising solution to meet the enormous energy demand in the future. The 15-15Ti austenitic stainless steel with outstanding corrosion and irradiation resistance has been proposed as main cladding candidate material for lead-bismuth fast reactor. However, the mechanical properties of 15-15Ti are weakly influenced by LBE. Shot peening as one of surface strengthening technique can efficiently improve metal mechanical properties. In this paper, shot peening (SP) treatment was applied on 15-15Ti. The microstructures and compositions were investigated using Optical Microscope, Scanning Electron Microscope and X-Ray Diffraction. It concludes that the material hardness is improved, and the residual stress induced by SP did not cause martensitic phase transformation on the sample surface. The presence of slip bands and other obstacles in the reinforcement layer improved the yielding and tensibility of the material.