Microstructure and Stresses in HVOF-Sprayed Iron Aluminide Coatings

Journal Article · Sun Sep 01 04:00:00 EDT 2002 · Journal of Thermal Spray Technology

DOI:https://doi.org/10.1361/105996302770348808· OSTI ID:912086

Totemeier, Terry Craig; Wright, Richard Neil; Swank, William David

The microstructure and state of stress present in Fe3Al coatings produced by high velocity oxygen fuel (HVOF) thermal spraying in air at varying particle velocities were characterized using metallography, curvature measurements, x-ray analysis, and microhardness measurements. Sound coatings were produced for all conditions. The microstructures of coatings prepared at higher velocities showed fewer unmelted particles and a greater extent of deformation. Residual stresses in the coatings were compressive and varied from nearly zero at the lowest velocity to approximately -450 MPa at the highest velocity. X-ray line broadening analyses revealed a corresponding increase in the extent of cold work present in the coating, which was also reflected in increased microhardness. Values of mean coefficient of thermal expansion obtained for as-sprayed coatings using x-ray analysis were significantly lower than those for powder and bulk alloy.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC07-99ID13727
• OSTI ID: 912086
• Report Number(s): INEEL/JOU-01-00192
• Journal Information: Journal of Thermal Spray Technology, Journal Name: Journal of Thermal Spray Technology Journal Issue: 3 Vol. 11
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS
COATINGS
DEFORMATION
HVOF
IRON
LINE BROADENING
METALLOGRAPHY
MICROHARDNESS
MICROSTRUCTURE
OXYGEN
RESIDUAL STRESSES
STRESSES
THERMAL EXPANSION
VELOCITY
coatings
iron aluminide
residual stress
thermal expansion
x-ray diffraction