Al Rich PVD Protective Coatings: A Promising Approach to Prevent T91 Steel Corrosion in Stagnant Liquid Lead

In order to investigate a protective coating approach for nuclear applications, two different aluminum rich layers were deposited on T91 steel coupons: Ti-Al-N films were grown via High Power Impulse Magnetron Sputtering and Al-O coatings were produced by Radio Frequency Magnetron Sputtering. In this exploratory work, coated specimens were corrosion tested in stagnant Pb at 550 degrees C for 1200 h and both types of coatings proved to be effective in protecting the substrate from the harsh environment. Due to the severe experimental conditions, the Al oxide film underwent some mechanical changes, while, the nitride coating demonstrated its noteworthy stability.