Abstract
Dislocation configurations in natural single crystals of CaTiO3 perovskite deformed in high-temperature creep were examined and characterized by transmission electron microscopy. Screw dislocations with Burgers vector [100]pc and [011]pc, dissociated on the \((01\bar 1)_{{\text{pc}}} \) plane, form rectangular networks with extended four-fold nodes in the shape of octagons, a configuration never observed in any of the previously investigated perovskites, except CaGeO3. Screw dislocations with Burgers vector [101]pc and \((\bar 101)_{{\text{pc}}} \) , on the (010)pc plane, react to form a twist wall; the dislocations with Burgers vector [002] produced by the reaction decompose into two perfect dislocations [001]pc. This results in a new configuration, never observed before, with three-fold nodes at the corners of rectangles. Both the octagonal extended nodes and the junctions decomposed into perfect dislocations are seen in samples deformed indifferently by slip on {100}pc or {110}pc planes, but they seem to appear only above 1520 K, in the cubic phase.
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Besson, P., Poirier, J.P. & Price, G.D. Dislocations in CaTiO3 perovskite deformed at high-temperature: a transmission electron microscopy study. Phys Chem Minerals 23, 337–344 (1996). https://doi.org/10.1007/BF00199499
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DOI: https://doi.org/10.1007/BF00199499