Charakterisierung des Warmumformverhaltens zweier Legierungen im System TiAl-Mo

Research output: ThesisDiploma Thesis

Abstract

In this diploma thesis the high temperature deformation behavior of two different cast and hot-isostatic pressed γ-TiAl-based alloys with different Al-contents (Ti-41Al-3Mo-0.5Si-0.1B, Ti-45Al-3Mo-0.5Si-0.1B) is investigated. Both alloys contain at room temperature the γ-TiAl, the βo-TiAl and small amounts of the α2-Ti3Al phase. To investigate the dynamic recovery and recrystallization during thermomechanical processing, isothermal compression tests are conducted on a Gleeble 3500 simulator and flow curves are measured. The tests are carried out at temperatures from 1150 °C to 1300 °C, applying strain rates ranging from 0.005 s-1 to 0.5 s-1 up to a true strain of 0.9. The deformed microstructural states of the multi-phased alloys, in particular the dynamically recrystallized grain size, are characterized with scanning electron microscopy and electron backscatter diffraction. The experimentally determined flow stress data are described with two different constitutive models (Sellars-Tegart, Hensel-Spittel). The experimentally determined grain sizes of the deformed microstructures are linked with the Zener-Hollomon-Parameter obtained from the simulation through a power law.

Details

Translated title of the contributionCharacterization of the high temperature deformation behaviour of two TiAl-Mo alloys
Original languageGerman
QualificationDipl.-Ing.
Supervisors/Advisors
Award date24 Oct 2014
Publication statusPublished - 2014