Rainbow test of advanced coatings for gas turbine blades and vanes

Technical Report · Fri Dec 01 04:00:00 EST 1989

OSTI ID:5202637

van Roode, M ^[1]

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1. Solar Turbines, Inc., San Diego, CA (USA)

The principal objective of this program was to carry out a comparative evaluation of the hot corrosion resistance of commercially available coatings applied to Ni-base blades and Co-base vanes in the hot section of an industrial gas turbine operating on a lower grade liquid fuel. The coatings evaluated included diffusion aluminides, metallic overlays, and a duplex ceramic overlay. This report summarizes the results of two Rainbow field tests performed for 7940 and 10,307 hours and details the results of the second test. The coatings were evaluated by visual observation, metallography, and coating thickness determinations. As a class MCrAlX (M = Co,NiCo; X = Y,Hf) low pressure plasma spray (LPPS) and electron beam physical vapor deposition (EB-PVD) overlay coatings showed the best overall protection against hot corrosion. MCrAlX blade coatings demonstrated superior hot corrosion resistance when compared with modified (Cr-,Pt(Rh)-) blade coatings in the low-temperature (Type 2) and intermediate (Type 1/2) temperature regimes of the lower blade sections. Pt-aluminides performed better in the high-temperature (Type 1) regime of the upper blade section approaching the hot corrosion resistance of the MCrAlX overlays. 34 refs., 53 figs., 17 tabs.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (USA); Solar Turbines, Inc., San Diego, CA (USA)
• Sponsoring Organization: EPRI
• OSTI ID: 5202637
• Report Number(s): EPRI-GS-6596
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200104* -- Fossil-Fueled Power Plants-- Components
36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
360105 -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
ALUMINIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
CHROMIUM ALLOYS
COATINGS
COBALT ALLOYS
COBALT BASE ALLOYS
COMPARATIVE EVALUATIONS
CORROSION
CORROSION RESISTANCE
CRYSTAL STRUCTURE
DOCUMENT TYPES
FAILURES
GAS TURBINE POWER PLANTS
GAS TURBINES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
MACHINERY
MATERIALS
MICROSTRUCTURE
NICKEL ALLOYS
OXIDES
OXYGEN COMPOUNDS
PLATINUM COMPOUNDS
POWER PLANTS
PROGRESS REPORT
RECOMMENDATIONS
SERVICE LIFE
TESTING
TRANSITION ELEMENT COMPOUNDS
TURBINE BLADES
TURBINES
TURBOMACHINERY
YTTRIUM COMPOUNDS
YTTRIUM OXIDES
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES