Coating Microstructure-Property-Performance Issues

Conference · Sun May 01 04:00:00 EDT 2005

OSTI ID:911122

Totemeier, Terry C; Wright, Richard N

Results of studies on the relationships between spray parameters and performance of thermally-sprayed intermetallic coatings for high-temperature oxidation and corrosion resistance are presented. Coating performance is being assessed by corrosion testing of free-standing coatings, thermal cycling of coating substrates, and coating ductility measurement. Coating corrosion resistance was measured in a simulated coal combustion gas environment (N2-CO-CO2-H2O-H2S) at temperatures from 500 to 800°C using thermo-gravimetric analysis (TGA). TGA testing was also performed on a typical ferritic-martensitic steel, austenitic stainless steel, and a wrought Fe3Al-based alloy for direct comparison to coating behavior. FeAl and Fe3Al coatings showed corrosion rates slightly greater than that of wrought Fe3Al, but markedly lower than the steels at all temperatures. The corrosion rates of the coatings were relatively independent of temperature. Thermal cycling was performed on coated 316SS and nickel alloy 600 substrates from room temperature to 800°C to assess the relative effects of coating microstructure, residual stress, and thermal expansion mismatch on coating cracking by thermal fatigue. Measurement of coating ductility was made by acoustic emission monitoring of coated 316SS tensile specimens during loading.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: DOE - FE
• DOE Contract Number: AC07-99ID13727
• OSTI ID: 911122
• Report Number(s): INL/CON-05-00416
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
ACOUSTICS
ALLOYS
COAL
COATINGS
COMBUSTION
CORROSION
CORROSION RESISTANCE
DUCTILITY
MICROSTRUCTURE
MONITORING
NICKEL ALLOYS
OXIDATION
STAINLESS STEELS
STEELS
SUBSTRATES
TESTING
THERMAL CYCLING
THERMAL EXPANSION
THERMAL FATIGUE
coatings
corrosion
intermetallic compounds