Absolute radiation tolerance of amorphous alumina coatings at room temperature

In this study structural and mechanical properties of a 1 μm thick Al2O3 coating, deposited on 316L stainless steel by Pulsed Laser Deposition (PLD), subjected to high energy ion irradiation were assessed. Mechanical pristine ion-modified specimens investigated using the nanoindentation technique. A comprehensive characterization combining Transmission Electron Microscopy Grazing-Incidence X-ray Diffraction provided deep insight into structure tested material at nano- micro-scale. Variation in local atomic ordering irradiated zone different doses was reduced distribution function analysis obtained from electron diffraction data. Findings measurements revealed slight reduction hardness all layers. At same time TEM examination indicated that layer remained amorphous over whole dpa range. No evidence crystallization, void formation or element segregation observed up highest implanted dose. Reported findings critically compared with each other pointing conclusion under given conditions, range used, alumina coatings exhibit excellent radiation resistance. Obtained data strongly suggest may be considered as promising candidate for next-generation nuclear reactors, especially LFR-type, where corrosion protection is one prerogatives met.