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Eigenschaftsoptimiertes Warmumformen einer intermetallischen Titanaluminid-Legierung

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Abstract

Die steigenden Anforderungen an Werkstoffe in Verbrennungsmotoren führen zum Einsatz innovativer Hochtemperaturleichtbauwerkstoffe mit geringer Dichte und hoher spezifischer Festigkeit bei hohen Temperaturen. Dieser Werkstoffklasse gehören auch intermetallische Titanaluminide an. Es handelt sich dabei um mehrphasige TiAl-Legierungen, deren komplexer Aufbau aus γ-TiAl, α2-Ti3Al und einem geringen Anteil an βo-TiAl Phase besteht. Durch gezielte Kombination von Wärmebehandlung und Warmumformung werden die mechanischen Eigenschaften optimiert, was vor allem auf den geringeren lamellaren Abstand innerhalb der α2/γ-Kolonien zurückzuführen ist. Die Untersuchungen der mechanischen Kennwerte aus Warmzug- und Kriechversuchen weisen auf das hohe Potential der intermetallischen Titanaluminide hin.

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