WIT Press


Softening Instability In Transformation Plasticity Of Zirconia-toughened Ceramics

Price

Free (open access)

Paper DOI

10.2495/LD960051

Volume

13

Pages

16

Published

1996

Size

1,199 kb

Author(s)

T.F. Guo & K.C. Hwang

Abstract

A micromechanics based continuum model, taking into account both di- latation and shear strain, is used to study the softening instability behavior of zirconia-toughened ceramics, such as the experimentally observed burst- like or autocatalytic transformation which is associated with a load drop. For a set of constitutive parameters, two deformation modes are examined, namely the onset of localization and the early exhaustion of transformation. The former arises traditionally as an indicator of bifurcations from homo- geneous deformation to localized one, while the latter is here referred as to an indicator of elastic unloadings under continuously increasing straining. Predictions of these two deformation modes on biaxially stretched sheets are shown to be strongly dependent upon the transformation-induced shear strain

Keywords