Stresses induced by differential sintering in powder compacts

Journal Article · Tue May 01 00:00:00 EDT 1984 · J. Am. Ceram. Soc.; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1984.tb19539.x· OSTI ID:6510436

Kellett, B; Lange, F F

Stress created by differential sintering, due to differences in initial bulk density, were determined, to an order of magnitude, by an experiment which estimated the differential sintering phenomenon on a macroscopic level. The experiments entailed determining the shrinkage rates of a powder isostatically pressed to two bulk densities. Using this information, stresses were determined by forcing the slower-densifying compact to shrink at the same rate as the faster-densifying compact and measuring the resulting forces with a load cell. Maximum stresses (between 1 and 3 MPa) were observed to occur in the intermediate stage of densification. Despite larger differential strains at higher temperatures, stresses decreased to zero at the latter stage of densification. Viscoelastic experiments, of the stress-relaxation type, were performed. Results showed that the sintering specimen was more rigid at lower temperatures and more fluid-like at higher temperatures. This explains the development of maximum stresses at intermediate temperatures.

• Research Organization: California Univ., Los Angeles
• OSTI ID: 6510436
• Journal Information: J. Am. Ceram. Soc.; (United States), Journal Name: J. Am. Ceram. Soc.; (United States) Vol. 67; ISSN JACTA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
CERAMICS
CHALCOGENIDES
COMPACTING
FABRICATION
OXIDES
OXYGEN COMPOUNDS
RELAXATION
SINTERING
STRESS RELAXATION
STRESSES
THERMAL STRESSES
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES