Experimental evaluation of chromium-carbide-based solid lubricant coatings for use to 760/sup 0/C

Technical Report · Sat Aug 01 04:00:00 EDT 1987

OSTI ID:6256976

Della Corte, C

This paper describes a research program to further develop and investigate chromium carbide based self-lubricating coatings for use to 760/sup 0/C. A bonded chromium carbide was used as the ''base stock'' because of the known excellent wear resistance and the chemical stability of chromium carbide. ''Additives'' were silver and barium fluoride/calcium fluoride eutectic. The three coating components were blended in powder form, applied to stainless steel substrates by plasma-spraying and then diamond ground to the desired coating thickness. A variety of coating compositions was tested to determine the coating composition which gave optimum tribological results. Coatings were tested in air, helium, and hydrogen at temperatures from 25 to 760/sup 0/C. Several counterface materials were evaluated with the objective of discovering a satisfactory metal/coating sliding combination for potential applications, such as piston ring/cylinder liner couples for Stirling engines. In general, silver and fluoride additions to chromium carbide reduced the friction coefficient and increased the wear resistance relative to the unmodified coating. The lubricant ''additives'' acted synergistically in reducing friction and wear. Several coating compositions gave good results in hydrogen, helium, and air to 760/sup 0/C.

• Research Organization: Case Western Reserve Univ., Cleveland, OH (USA)
• DOE Contract Number: AI01-86CE50162
• OSTI ID: 6256976
• Report Number(s): DOE/NASA-0030-2; NASA-CR-180808; ON: DE87014296
• Country of Publication: United States
• Language: English

Related Subjects

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36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360203 -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM FLUORIDES
CALCIUM COMPOUNDS
CALCIUM FLUORIDES
CALCIUM HALIDES
CARBIDES
CARBON COMPOUNDS
CHROMIUM CARBIDES
CHROMIUM COMPOUNDS
DATA
DEPOSITION
ELEMENTS
EUTECTICS
EXPERIMENTAL DATA
FLUORIDES
FLUORINE COMPOUNDS
FRICTION
HALIDES
HALOGEN COMPOUNDS
HIGH TEMPERATURE
INFORMATION
LUBRICANTS
METALS
NUMERICAL DATA
PLASMA ARC SPRAYING
SILVER
SLIDING FRICTION
SOLID LUBRICANTS
SPRAY COATING
SURFACE COATING
TESTING
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TRIBOLOGY
WEAR