Nitridation of a Super-Ferritic Stainless Steel for PEMFC Bipolar Plate

Heli Wang, John A. Turner, Mike P. Brady

Research output: Contribution to journalArticlepeer-review

6 Scopus Citations


AL29-4C alloy nitrided in pure nitrogen resulted in a nitrogen-modified oxide surface, which is the same as AISI446 nitrided under identical conditions. When the alloy was nitrided 24h at 900°C in N2-4H2, XRD and XPS analysis indicated that the surface layer consisted of a nitride outer layer (∼0.20 μm) and an oxide inner layer (∼0.82 μm). According to XPS, the nitride outer layer is composed of CrN and [Cr(N),Fe] 2N1-x, with much more Cr2N than Fe 2N. Mn is migrated and enriched in the oxide inner layer and combined with chromium oxide. AL29-4C alloy nitrided in N2-4H2 resulted in low ICR and excellent corrosion resistance in simulated PEMFC environments. Current was at ca. -3.0 μA/cm2 in the PEMFC anode environment, and at ca. 0.3 - 0.5 μA/cm2 in the cathode environment. This is considered to be rather stable. After being polarized in a PEMFC environment, the ICR increased slightly compared with the as-nitrided sample, but was still rather low.

Original languageAmerican English
Pages (from-to)1461-1471
Number of pages11
JournalECS Transactions
Issue number1
StatePublished - 2007
Event7th Symposium Devoted to Proton Exchange Membrane Fuel Cells - 212th ECS Meeting - Washington, DC, United States
Duration: 7 Oct 200712 Oct 2007

NREL Publication Number

  • NREL/JA-560-41875


Dive into the research topics of 'Nitridation of a Super-Ferritic Stainless Steel for PEMFC Bipolar Plate'. Together they form a unique fingerprint.

Cite this