Outokumpu Oy, Finland, is expanding its product range with two new high-chromium stainless steel grades, ferritic grade EN 1.4622 and austenitic grade EN 1.4420. The ferritic grade Outokumpu 4622 is its first high-chromium ferritic grade, while the new austenitic Outokumpu 4420 grade is completely new in the market. Both grades are said to offer benefits in corrosion resistance, strength, and formability.
The ferritic 4622 grade is suitable for demanding applications such as façades, elevators, and automotive. It has similar corrosion resistance but better deep-drawability than the standard 304 grade. The austenitic 4420 grade is acid-resistant and is designed for applications in heavy industries such as construction, pulp and paper, and structures, piping, and water treatment applications. Compared to 316L, it has improved corrosion resistance and higher strength.
The ferritic steel grade fulfills ASTM UNS S44330 requirements, and work is in progress for EN standardization. For the austenitic high-chromium grade, both ASTM and EN standardization is ongoing. Outokumpu has conducted pilot tests for both grades and they are now available.
