Development of spacecraft materials and structures fundamentals. Final scientific report, 1 June 1984-31 May 1985

Technical Report · Thu Aug 01 04:00:00 EDT 1985

OSTI ID:6148151

Prochazka, S; Dole, S L

Compacts of boron carbide powders with specific surface area = or > 8 sq m/g were sintered in argon at temperatures near 2200 C. Several of these powders were prepared by attrition milling of abrasive-grade boron carbide. Densification to 95+% of theoretical denstiy could be obtained only with compositions that had appropriate amounts of excess carbon. The microstructures were fined-grained and uniform but underwent abnormal grain growth above 2235 C accompanied by transgranular microcracking. This grain growth could be inhibited by increasing the carbon content. Mechanical damping capacity was measured by the free beam and cantilevered beam techniques on boron carbide and other materials. Methods to enhance the damping capacity in a beam structure were analyzed. The flexural strength of sintered boron carbide was evaluated and related to powder processing and sintering parameters.

• Research Organization: General Electric Co., Schenectady, NY (USA). Corporate Research and Development Center
• OSTI ID: 6148151
• Report Number(s): AD-A-161338/9/XAB; SRD-85-021
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
ARGON
BORON CARBIDES
BORON COMPOUNDS
CARBIDES
CARBON
CARBON COMPOUNDS
COMPACTING
CRYSTAL STRUCTURE
CUTTING
DAMPING
ELEMENTS
FABRICATION
FLEXURAL STRENGTH
FLUIDS
GASES
GRAIN GROWTH
MACHINING
MECHANICAL PROPERTIES
MICROSTRUCTURE
NONMETALS
RARE GASES
SINTERING
SURFACES
VERY HIGH TEMPERATURE