Superplasticity of TZP/AI₂O₃Composite

Abstract

The superplastic behavior of the composite Y-TZP/Al{sub 2}O{sub 3} (20 wt%) in uniaxial tension has been evaluated. Large elongation (>200%) indicated superplasticity. The stress exponent and activation energy of thee composite were found to be the same order with those of Y-TZP. The flow behavior of the composite containing Al{sub 2}O{sub 3} grains could be described by a rheological model as a non-Newtonian flow modified by the second-phase grains. The cavitation damage and the creep crack growth could be reduced by keeping the strain rate low enough that a specimen elongated 100% at elevated temperature maintained a strength of 1,800 MPa at room temperature.