Nanometer-scaled lamellar microstructures in Ti–45Al–7.5Nb–(0; 0.5)C alloys and their influence on hardness

作者: Limei Cha , Christina Scheu , Helmut Clemens , Harald F. Chladil , Gerhard Dehm

DOI: 10.1016/J.INTERMET.2008.03.009

关键词: Volume fractionAnnealing (metallurgy)Transmission electron microscopyLamellar structureNanometreMicrostructureComposite materialMaterials scienceMetallurgy

摘要: Abstract In this study, nanometer-scaled lamellar microstructures were adjusted in Ti–45Al–7.5Nb–(0; 0.5C) alloys (in at.%) and analyzed by means of transmission electron microscopy. Different annealing temperatures subsequent to quenching used obtain well-defined with ultrafine widths a few tens nanometers nanometers. Surprisingly, the hardness these is enhanced increasing volume fraction γ-TiAl laths. This behavior different from results reported literature can be explained occurrence size effect. The nanometer-size γ laths became harder than α 2 -Ti 3 Al which are 10 times wider.

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