Plasticity and an inverse brittle-to-ductile transition in strontium titanate.
The use of ceramic materials is often restricted by a transition from ductile behavior to brittle fracture with decreasing temperature. For example, strontium titanate ( SrTiO3) is known to be extremely fragile and brittle below 1300 K. It is therefore surprising to find that SrTiO3 single crystals can be deformed in compression below 1050 K again. Extensive plastic deformation up to 7% strain at low yield stresses of the order of only 120 MPa is possible at room temperature. Low temperature plasticity is carried by the same [110] [110] dislocations as the high temperature deformation along the [001] axis. From this we conclude that these dislocations must exist in two different core configurations.
Gumbsch
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Max-Planck-Institut für Metallforschung, Seestrasse 92, 70174 Stuttgart, Germany.
Taeri-Baghbadrani
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Brunner
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Sigle
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Rühle
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