Microstructural effects on the residual stress and stress distribution in WC-Ni composites

Thesis/Dissertation · Mon Jan 01 04:00:00 EST 1990

OSTI ID:5642303

Seol, K

Effects of microstructure on the differential thermal residual stresses and their distributions for model WC-Ni cemented carbide composites were determined by neutron powder diffraction. Absolute strain and stress values were obtained from the difference in WC cell parameters in a stress-free, loose WC powder and the WC phase in the composite over the temperature range 100 to 900 K. The resultant volume averaged strains in the hexagonal WC particles were highly anisotropic, with the strains in the a-direction exceeding those in the c-direction. This was correctly predicted by Eshelby's equivalent inclusion method assuming the particle shape as an oblate spheroid. In addition, the strain distribution in the WC and Ni binder phases were determined by a modified integral peak breadth method of particle size-strain analysis using the peak breadths in the reference powder and the composite. Strain distribution cannot be converted into stress distribution directly because the stresses due to the WC particle aspect ratio are not hydrostatic and because the fraction of each effect on the total strain distribution is not known. Therefore, quantitative stress distribution values were not determined.

• Research Organization: Missouri Univ., Columbia, MO (United States)
• OSTI ID: 5642303
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALLOYS
CARBIDES
CARBON COMPOUNDS
COHERENT SCATTERING
COMPOSITE MATERIALS
CRYSTAL STRUCTURE
DIFFRACTION
FIBERS
MATERIALS
MICROSTRUCTURE
NEUTRON DIFFRACTION
NICKEL ALLOYS
NICKEL BASE ALLOYS
REFRACTORY METAL COMPOUNDS
SCATTERING
STRESS ANALYSIS
TEMPERATURE EFFECTS
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN CARBIDES
TUNGSTEN COMPOUNDS