COMPRESSIVE PROPERTIES OF YTTRIUM-OXIDE

Compressive properties of polycrystalline yttrium oxide (Y2O3) were st udied by slow-strain-rate experiments (epsilon = 5.7 x 10(-6) s(-1)) b etween room temperature and 1600 degrees C. It was shown that Y2O3 fai ls in a brittle manner up to 1000 degrees C, and at 1200 degrees C and above plastic deformation becomes dominant. Plastic deformation of Y2 O3 takes place exclusively by dislocation motion. Maximum stress, yiel d stress, and elastic modulus decrease with increasing temperature, al though the decrease at temperatures above 1000 degrees C is much more pronounced.