Performance of aluminide coatings applied on alloy CF8C plus at 800 C

Conference · Sat Jan 01 00:00:00 EST 2011

OSTI ID:1024650

Kumar, Deepak ^[1]; Dryepondt, Sebastien N ^[1]; Shyam, Amit ^[1]; Haynes, James A ^[1]; Pint, Bruce A ^[1]; Armstrong, Beth L ^[1]; Lara-Curzio, Edgar ^[1]

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1. ORNL

The cost effective, austenitic stainless steel CF8C plus is an attractive alloy for massive cast structures such as steam turbine casings. The microstructure stability and creep strength of this alloy are better than commercial high-performance heat-resistant steels such as NF709 and Super 304H, and are comparable to the Ni-based superalloy Inconel 617. The oxidation resistance of the alloy in atmosphere rich in water vapor is however insufficient at T>800 C, and the use of diffusion aluminide coatings is considered for potential high temperature applications. The thermal stability and protectiveness of coatings applied on the CF8C plus substrate by pack cementation and slurry process were investigated in air + 10% H2O environment at 800 C. Further, the coating effect on the fatigue life of the alloy was assessed via low-cycle-fatigue experiments.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Temperature Materials Lab. (HTML)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1024650
• Resource Relation: Conference: Corrosion 2011, Houston, TX, USA, 20110313, 20110317
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AIR
ALLOYS
COATINGS
CORROSION
CREEP
DIFFUSION
HEAT RESISTING ALLOYS
INCONEL 617
MICROSTRUCTURE
OXIDATION
PERFORMANCE
STABILITY
STAINLESS STEELS
STEAM TURBINES
STEELS
SUBSTRATES
WATER VAPOR