UNS N08935 is a newly developed alloy with limited available corrosion data. Due to its high content of alloying elements – especially chromium, molybdenum and nickel – it can be expected to be a candidate alloy in many highly corrosive environments where uniform corrosion is expected to be the main mode of corrosion. In this work, the uniform corrosion resistance of UNS N08935 has been evaluated in several different environments, including commonly found acids such as sulfuric acid, hydrochloric acid, organic acids, and others. Results from different test methods will be presented and compared to other alloys. The presented data can aid in material selection processes, as well as guide future testing in other conditions.
Highly alloyed stainless steels and Ni-based alloys may be used in a wide range of different chemical environments. By investigating how different alloys are affected by environmental changes – be it chemical composition, temperature, contaminants or others – it is possible to learn more about how material selection can be optimized to improve both cost efficiency and longevity of a system.
UNS N08935 is a highly alloyed austenitic material in the borderland between stainless steels and Ni-based alloys. Being a relatively new grade to the market, there is still a lot of potential to find usage areas and niches where this grade might offer improved performance or economics compared to established grades. Mechanical, physical and corrosion properties of N08935 have been described previous works.1 The results indicate a good resistance to common acids, such as sulfuric, hydrochloric, nitric, and organic acids, as well as a very high resistance to pitting corrosion, crevice corrosion and stress corrosion cracking. The localized corrosion resistance has been studied further and compared to established grades such as UNS N06625 and UNS N10276.2-3 Results from both laboratory tests and exposures to natural and chlorinated seawater indicate that N08935 could be a suitable alternative to such materials in conditions where pitting and crevice corrosion are the main risks.
