Effect of ion polishing on corrosion resistance of the cladding of fuel elements from E110 alloy in the steam water environment

Behaviour of Ion-modified Cladding Tubes from E110 Alloy in High-temperature Water Steam

“…SEM image of the E110opt sample outer surface coated by FeCrNi atoms 2-4 μm thick after oxidation in 800/5000 mode near the crack. a b Typical images of the transverse structure of oxide films on samples of the alloy E110opt in the initial state (a) and doped Fe (б) after oxidation in 1000/5000 mode.MIE-2017ion polishing on the defectiveness of oxide films is due to decrease surface roughness, smoothing of the defects of the tubes rolling process and accompanied by decrease in density of growth defects in the oxide as pores and microcracks and their size.The beneficial effect of ion polishing on the growth of oxide films has been shown previously[5,6].Autoclaving of the samples under conditions close to the operational ones for WWER (water temperature 350 ∘ C, pressure 16.5 MPa with exposure to 400 h) made it possible to note a significant decrease of average specific weight gain on the modified samples in comparison with initial samples: ion polishing -by 49%; alloying Fe -by 13%; alloying Fe+Mo -by 39%; alloying Fe+Y -by 35%; alloying Fe+Y + coating Y 2 O 3 -by 76%. In addition, there are practically no cracks that are observed on samples with an untreated surface on the surface of samples that have undergone ion polishing and iron doping, after the high-temperature oxidation in 800/5000.…”

High-Temperature Oxidation of Cr-Coated Resistance Upset Welds Made from E110 Alloy

“…Thus, the additional posttreatment of the RUW welds should be needed to decrease surface roughness of weld burr and uniform coating deposition. For this purpose, mechanical processing, chemical etching [21] or ion-plasma treatment [41] can be considered. It should be noted that lower oxidation kinetics of E110 alloy in the border of uncoated and Cr-coated regions also like as lower oxide thickness in the defect region of weld burr in the case of the fully Cr-coated samples.…”