|About this Abstract
||Materials Science & Technology 2020
||Engineered Phase Transformations
||Grain Size-effect on the Survivability of Shape Memory Zirconia during Cyclic Martensitic Transformations
||Isabel R. Crystal, Christopher A. Schuh
|On-Site Speaker (Planned)
||Isabel R. Crystal
Shape memory ceramics (SMCs) can crack as they undergo their martensitic transformation from the tetragonal to the monoclinic phase, especially in bulk sample sizes and polycrystalline structures that enhance mismatch stresses. Polycrystalline samples can crack intergranularly and bodily lose grains during cyclic martensitic transformations, and here we explore such degradation as a function of grain size over a range from 0.6 to 7.9 Ám for a pellet of a fixed diameter of ~5 mm. Smaller grain sizes are found to slow the rate of disaggregation of the pellet, an effect which we analyze by performing quantitative calorimetry. When such calorimetry analysis is conducted over a large number of transformation cycles, it permits an assessment of the evolution of heat flow as the pellets degrade into a granular packing of loose grains.