Mechanical double loop behavior in BaTiO3: Stress induced paraelastic to ferroelastic phase transformation

The structural origin of the mechanical double loop behavior of polycrystalline BaTiO3 at temperatures just above the Curie point has been investigated using in situ high-energy synchrotron x-ray diffraction during uniaxial compressive mechanical loading. The results show a stress-induced transition from the high temperature paraelastic cubic phase to a ferroelastic tetragonal phase with a domain texture close to the saturated state. The nature of the observed stress-induced phase transition was influenced by the proximity of the temperature to the Curie point. With increasing temperature above the Curie point, the transition stress increased while the rate of the transition decreased. (C) 2013 AIP Publishing LLC.