Interdiffusion Behavior of Aluminide Coatings on Fe-Base Alloys

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Materials and Corrosion

DOI:https://doi.org/10.1002/maco.200704057· OSTI ID:931922

Zhang, Ying ^[1]; Liu, A. P. ^[1]; Pint, Bruce A ^[2]

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1. Tennessee Technological University
2. ORNL

One of the potential degradation modes of oxidation-resistant iron aluminide coatings is the loss of Al from the coatings into Fe-base substrate alloys that typically contain no Al. To address this issue, interdiffusion between aluminide coatings and steel substrates was studied for times up to 10,000 h in the temperature range of 500-800 C. Coatings were synthesized in a laboratory chemical vapor deposition (CVD) reactor on representative commercial ferritic alloy Fe-9Cr-1Mo and type 304L austenitic stainless steel. The microstructural and compositional changes after diffusion anneals were examined in detail. An initial attempt to model the interdiffusion behavior was carried out by applying an existing software program COSIM (coating oxidation and substrate interdiffusion model). Complementary work was conducted using a simple mathematic model developed by Heckel et al. Reasonable agreement was observed between the simulated and experimental composition profiles for the aluminide coatings on ferritic alloys. Model results were then applied to predict coating lifetime.

• Research Organization: Oak Ridge National Laboratory (ORNL); High Temperature Materials Laboratory; Shared Research Equipment Collaborative Research Center
• Sponsoring Organization: FE USDOE - Office of Fossil Energy (FE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 931922
• Journal Information: Materials and Corrosion, Journal Name: Materials and Corrosion Journal Issue: 10 Vol. 58; ISSN 0947-5117; ISSN MTCREQ
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM
Aluminide
CHEMICAL VAPOR DEPOSITION
COATINGS
Coatings
DIFFUSION
IRON
IRON BASE ALLOYS
Interdiffusion
LIFETIME
Model
OXIDATION
Oxidation
STAINLESS STEELS
STEELS
SUBSTRATES