Oxidation behavior of ferritic stainless steels in simulated automotive exhaust gas containing 5 vol.% water vapor

In the attempt to develop materials for interconnects of planar-type solid oxide fuel cells (SOFC), the oxidation behavior and scale electrical properties of four, commercially available, ferritic stainless steels were investigated by oxidizing at 800°C for times up to 900 h in the dry and wet air environments. The growth kinetics of oxide scales were significantly deviated from the parabolic growth law, exhibiting the temporal growth exponent being much less than 0.5. Titanium addition in ferrite stainless steels was detrimental to oxidation resistance since its fast out-diffusion onto the scale surface enhanced the scale growth. For the alloys without Ti contents, the presence of water vapor in the oxidizing environment enhanced the scale growth rate, but it resulted in a drastic, microstructural change of oxide scale that consisted of Cr2MnO4 spinel and Cr2O3, which in turn lowered the area specific resistance (ASR) and the apparent activation energy for conduction.

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Effect of Water Vapor in Air on the Oxidation Behavior of Ferritic Stainless Steels for SOFC Interconnects

THERMEC 2006 Supplement - Advanced Materials Research ◽

10.4028/0-87849-429-4.305 ◽

2006 ◽

pp. 305-309

Author(s):

J.H. Chung ◽

Joo Youl Huh ◽

Jae Ho Jun ◽

D.H. Kim ◽

Joong Hwan Jun

Keyword(s):

Water Vapor ◽

Stainless Steels ◽

Oxidation Behavior ◽

Ferritic Stainless Steels ◽

Effect Of Water

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J & L TYPE 409/409 HP

Alloy Digest ◽

10.31399/asm.ad.ss0743 ◽

1999 ◽

Vol 48 (5) ◽

Keyword(s):

Corrosion Resistance ◽

Physical Properties ◽

Tensile Properties ◽

Stainless Steels ◽

Heat Treating ◽

Automotive Exhaust ◽

Ferritic Stainless Steels ◽

Resistance To Oxidation ◽

Specialty Steel ◽

Oxidation And Corrosion

Abstract J and L Types 409 HP are ferritic stainless steels with 11% chromium. They exhibit an excellent combination of good formability, economy, and resistance to oxidation and corrosion. It is typically used in automotive exhaust systems. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-743. Producer or source: J & L Specialty Steel Inc.

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Corrosion Evaluation of Ferritic Stainless Steels for Automotive Exhaust Applications

CORROSION ◽

10.5006/3319 ◽

2019 ◽

Vol 75 (11) ◽

pp. 1276-1280

Author(s):

Y. Emun ◽

H.S. Zurob ◽

J.R. Kish

Keyword(s):

Stainless Steels ◽

Localized Corrosion ◽

Bench Mark ◽

Neutral Salt ◽

Automotive Exhaust ◽

Metallographic Examination ◽

Ferritic Stainless Steels ◽

Corrosion Evaluation ◽

Corrosion Susceptibility ◽

Salt Fog

This study compares the localized (exterior) corrosion susceptibility of chromized steel to bench-mark ferritic stainless steels for automotive exhaust applications. Continuous near-neutral salt fog exposure (ASTM B117) was used for this purpose. Corrosion susceptibility was determined using mass loss measurements coupled with a post exposure metallographic examination. Complementary potentiodynamic polarization measurements were made in the bulk salt solution to help interpret the relative performance. The elevated Cr content provided by the chromizing surface treatment provides comparable corrosion resistance to the more highly alloyed ferritic stainless steels studied. The major factor affecting localized corrosion susceptibility is the formation of rust deposits, which act as effective pit-like corrosion initiation sites.

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