POSCO Holdings Inc.
STAINLESS STEEL HAVING EXCELLENT CONTACT RESISTANCE FOR PEMFC SEPARATOR AND METHOD OF MANUFACTURING THE SAME

Abstract:

Stainless steel having excellent contact resistance for a PEMFC separator and a method for manufacturing the stainless steel are disclosed. The stainless steel for the Polymer Electrolyte Membrane Fuel Cell (PEMFC) separator according to an embodiment of the present disclosure may include: by weight percent, 0 to 0.02% of C (excluding 0%), 0 to 0.02% of N (excluding 0%), 0 to 0.25% of Si (excluding 0%), 0% to 0.2% of Mn (excluding 0%), 0 to 0.04% of P (excluding 0%), 0 to 0.02% of S (excluding 0%), 25 to 34% of Cr, 0 to 0.5% of Ti (excluding 0%), 0 to 0.5% of Nb (excluding 0%), 0 to 0.6% of Sn (excluding 0%) and the remainder comprising iron (Fe) and other unavoidable impurities, wherein the value of the following formula (1) with respect to the atomic ratio of X and Sn in the region within 3 nm in thickness from a surface of a passive film is 0.001 or more. X/Sn formula (1) Where X is Cl or F.