Processing and characterization of transformation-toughened ceramics with strength retention to elevated temperatures. Final report
- Ceramatec, Inc., Salt Lake City, UT (United States)
- Univ. of Utah (United States)
Monolithic and three-layered Al{sub 2}O{sub 3} -- 15 vol % ZrO{sub 2} composites were fabricated by slip casting aqueous slurries. The outer and inner layers of three-layer composites contained unstabilized and partially stabilized ZrO{sub 2}, respectively. Transformation of part of the unstabilized ZrO{sub 2} led to surface compressive stresses in the outer layers. Strain gage, x-ray, indentation crack length, and strength measurements were used to determine the magnitude of residual stresses in the composites. The strength of the three-layer composites ({approx}1200 MPa) was 500--700 MPa higher than that of the monolithic outer layer composites at room temperature and 350 MPa higher at 750{degree}C. The strength differential decreased rapidly above the m {yields} t transformation temperature. Three-layered composites showed excellent damage resistance and improved reliability. Cam follower rollers were fabricated to demonstrate the applicability of this technique for making automotive components.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ceramatec, Inc., West Valley City, UT (United States
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 10113865
- Report Number(s):
- ORNL/Sub-85-22028/2; ON: DE95005758
- Resource Relation:
- Other Information: PBD: Sep 1994
- Country of Publication:
- United States
- Language:
- English
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