Aggressive corrosion of C-276 nickel superalloy in chloride/sulphate eutectic salt

Molten salts are often used to store thermal energy in concentrating solar power plants. The need for higher temperature storage systems has prompted investigation into and structural alloys use at temperatures. A eutectic mixture of 68.05 wt% Na2SO4: 31.95 NaCl salt is a potential phase change material such systems, with low cost high latent heat fusion. This paper investigates corrosion Inconel C-276 nickel alloy this under air argon atmospheres. It was found that aggressively corroded rate calculated as 64 mm/year, complex unique structure observed. When tested argon, even more severe, the sample completely consumed 5 days. result attributed basic mechanism which attacked chromium iron, whilst sulphur nickel. molybdenum tungsten content not present significant concentration product, possibly because these elements formed chloride-based compounds evaporated. reinforces oxygen containing can be highly corrosive, resistant superalloys inert