High-strain-rate superplasticity in oxide ceramics

Keijiro Hiraga, Byung Nam Kim, Koji Morita, Hidehiro Yoshida, Tohru S. Suzuki, Yoshio Sakka

Research output: Contribution to journalReview article

28 Citations (Scopus)

Abstract

Factors limiting the strain rate of superplastic deformation in ceramic materials are discussed on the basis of existing models and experimental results concerning high-temperature plastic deformation, intergranular cavitation and dynamic grain growth. From the discussion, it is indicated that simultaneously fulfilling the following conditions is essential for attaining high-strain-rate superplasticity (HSRS) in ceramic materials: reduction in the initial grain size, enhanced diffusivity, suppressed dynamic grain growth, a homogeneous microstructure and a reduced number of residual defects. In the light of these conditions, explanations are given for HSRS attained in earlier studies on some oxide materials. It is also shown that HSRS can be intentionally attained in doped yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) and composites synthesized from ZrO2, Al2O3 and MgO2; the tensile ductility of these composites reached 300-2500% at a strain rate of 0.01-1.0 s-1. The postdeformation microstructure indicates that some secondary phases may suppress cavitation damage and thereby enhance HSRS.

Original languageEnglish
Pages (from-to)578-587
Number of pages10
JournalScience and Technology of Advanced Materials
Volume8
Issue number7-8
DOIs
Publication statusPublished - 2007 Oct 1
Externally publishedYes

Keywords

  • Cavitation
  • Diffusion
  • Grain growth
  • High-strain rate
  • Stress relaxation
  • Superplasticity

ASJC Scopus subject areas

  • Materials Science(all)

Fingerprint Dive into the research topics of 'High-strain-rate superplasticity in oxide ceramics'. Together they form a unique fingerprint.

  • Cite this