Significance of internal stresses for the martensitic transformation in yttria-stabilized tetragonal zirconia polycrystals during degradation

Journal Article · Tue Jul 01 00:00:00 EDT 1986 · J. Am. Ceram. Soc.; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1986.tb04789.x· OSTI ID:7067276

Schmauder, S; Schubert, H

Various aspects of the tetragonal (t) to monoclinic (m) transformation during degradation have been studied experimentally and theoretically in yttria-stabilized tetragonal zirconia polycrystals (Y-TZP), i.e., polycrystalline t-ZrO/sub 2/ containing Y/sub 2/O/sub 3/ in solution. Transmission electron microscopy (TEM) revealed that protruding grains at the surface of Y-TZP specimens do not transform under corrosive conditions (250/sup 0/C, humid atmosphere) even after n annealing time of 168 h.) Eigenstresses due to anistropic thermal expansion in and around protruding and bulk grains have been calculated for Y-TZP containing 2 and 3 mol% Y/sub 2/O/sub 3/. The prominent role of these stresses on subsequent transformation nucleation during degradation is shown to agree qualitatively with an established free energy concept. The lack of complete transformation of m-ZrO/sub 2/ is attributed to characteristics of the nucleation - and growth- controlled transformation process.

• Research Organization: Max-Planck-Institut fur Metallforschung, Institut fur Werkstoffwissenschaften, Stuttgart
• OSTI ID: 7067276
• Journal Information: J. Am. Ceram. Soc.; (United States), Vol. 69:7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
YTTRIUM OXIDES
ANNEALING
PHASE TRANSFORMATIONS
STRESSES
ZIRCONIUM OXIDES
ANISOTROPY
CORROSION
GRAIN SIZE
HIGH TEMPERATURE
MARTENSITE
NUCLEATION
POLYCRYSTALS
RESEARCH PROGRAMS
THERMAL EXPANSION
TIME DEPENDENCE
TRANSMISSION ELECTRON MICROSCOPY
ALLOYS
CARBON ADDITIONS
CHALCOGENIDES
CHEMICAL REACTIONS
CRYSTAL STRUCTURE
CRYSTALS
ELECTRON MICROSCOPY
EXPANSION
HEAT TREATMENTS
IRON ALLOYS
MICROSCOPY
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
SIZE
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
ZIRCONIUM COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies
360203 - Ceramics
Cermets
& Refractories- Mechanical Properties
360201 - Ceramics
Cermets
& Refractories- Preparation & Fabrication