Herstellung und Eigenschaften Al-reicher TiAl Legierungen

Autor :Daniel Sturm
Herkunft :OvGU Magdeburg, Fakultät für Maschinenbau
Datum :27.08.2010
Dokumente :
Dataobject from HALCoRe_document_00008890
Typ :Dissertation
Format :Text
Kurzfassung :Compared to Ti-rich gamma-TiAl-based alloys Al-rich TiAl alloys offer an additional reduction of 20% in density and a better oxidation resistance which are both due to the increased Al content. Polycrystalline material of two binary alloys, namely Al60Ti40 and Al62Ti38 and a ternary Al62Ti36Nb2 alloy was manufactured by centrifugal casting. Selected single-crystal samples were also produced by directional solidification. The alloys were investigated in the cast condition (containing various amounts of the metastable phases Al5Ti3 and h-Al2Ti) and after annealing at 950 °C for 200 h which produced (thermodynamically stable) lamellar gamma-TiAl + r-Al2Ti microstructures. Microstructure characterization was carried out employing light-optical, scanning and transmission electron microscopy, and XRD analyses. The high temperature creep strength was assessed with compression tests at constant true stress in the temperature range from 900 to 1050 °C in air. In addition a numerical and analytical calculation of steady state stresses and strains in three point bending creep tests is presented. The fracture toughness was investigated using Vickes indention tests and notched three point bending test.
Schlagwörter :TiAl alloys, Microstructure, TEM, Creep
Rechte :Dieser Text ist urheberrechtlich geschützt
Größe :117 S.
Erstellt am :02.11.2010 - 12:38:44
Letzte Änderung :02.11.2010 - 12:39:48
MyCoRe ID :HALCoRe_document_00008890
Statische URL :http://edoc.bibliothek.uni-halle.de/servlets/DocumentServlet?id=8890