Stainless steel having excellent contact resistance or pemfc separator an method of manufacturing same

Abstract

Disclosed are a stainless steel for a fuel cell separator and a method of manufacturing the same. The stainless steel has a low contact resistance as a material for a fuel cell separator and surface roughness parameters that may represent a surface shape of the stainless steel are defined and provided. Specifically, the present disclosure provides a stainless steel for a fuel cell separator with excellent contact resistance and a method of manufacturing the same. The stainless steel includes, in percent by weight (wt %), more than 0 but not more than 0.02% of C, more than 0 but not more than 0.02% of N, more than 0 but not more than 0.4% of Si, more than 0 but not more than 0.3% of Mn, more than 0 but not more than 0.04% of P, more than 0 but not more than 0.02% of S, 15 to 34% of Cr, more than 0 but not more than 1% of Cu, more than 0 but not more than 0.4% of Ni, more than 0 or not more than 0.5% of at least one of Ti and Nb, and the balance of Fe and inevitable impurities, wherein at least one surface has a three-dimensional arithmetic average roughness (Sa) of 0.05 μm or more and a developed interfacial area ratio (Sdr) of 5% or more.

Dependencies are inferred from the claim text.