Super Duplex 2507 (F53 / 1.4410 / UNS S32750) By yaang.com

Super Duplex 2507 (F53 / 1.4410 / UNS S32750) has excellent corrosion resistance to a wide variety of media, with outstanding resistance to pitting and crevice corrosion in seawater and other chloride containing environments, with Critical Pitting Temperature exceeding 50°C.UNS S32750 (F53 / 1.4410 / Alloy 2507) exhibits a low coefficient of thermal expansion and higher heat conductivity than austenitic steels and is suitable for working temperatures up to 300°C.

Selection Stainless Steel for Handling Sulphuric Acid H2SO4 By yaang.com

Sulphuric acid is oxidising when concentrated but is reducing at low and 'intermediate' concentrations.

The response of most stainless steel types is that in general they are resistant at either low or high concentrations, but are attacked at intermediate concentrations. Commercially concentrated acid is around 96 wt % (sg = 1.84).

The improvement in corrosion resistance moving from stainless steel 304 /1.4301 to 316 / 1.4401 is due to the addition of molybdenum. Further additions of moybdenum and copper in the 1.4539 904L grade extend the corrosion resistance in these reducing acid conditions. The molybdenum in types 316 stainless steel and grade 1.4539 also helps improve resistance to chloride attack, when present as impurities in the acid.

1.4410 2507 S32750 Super Duplex Stainless Steel By yaang.com

2507 S32750 Super Duplex Stainless Steel is super duplex stainless steel with 25% chromium, 4% molybdenum, and 7% nickel designed for demanding applications which require exceptional strength and corrosion resistance, such as chemical process, petrochemical, and seawater equipment. The steel has excellent resistance to chloride stress corrosion cracking, highthermal conductivity, and a low coefficient of thermal expansion. 

Super duplex stainless steel grades have enhanced pitting and crevice corrosion resistance when compared with 300-series austeniticstainless steel or conventional duplex alloys. This can be attributed to the enhanced levels of chromium, molybdenum and nitrogen found in these materials. Alloy 2507 is the most common “super” duplex grade.