Cyclic plasticity and strain localization in cast Gamma-TiAl based alloy

0397311 - ÚFM 2014 RIV NL eng C - Konferenční příspěvek (zahraniční konf.)
Petrenec, Martin - Polák, Jaroslav - Buček, Petr
Cyclic plasticity and strain localization in cast Gamma-TiAl based alloy.
11th International conference on the Mechanical Behavior of Materials (ICM). Amsterdam: Elsevier, 2011, s. 1390-1395. Procedia Engineering, 10. ISSN 1877-7058.
[ICM11 -International Conference on The Mechanical Behavior of Materials /11./. Lake Como (IT), 05.06.2011-09.06.2011]
Grant CEP: GA ČR(CZ) GAP107/11/0704
Klíčová slova: low cycle fatigue * lamellar TiAl alloy * loop shape parameter * peristent slip marketing
Kód oboru RIV: JJ - Ostatní materiály

Cyclic strain localization and observation of surface relief in nearly lamellar cast Gamma-TiAl based alloy Ti–48Al–2Nb–2Cr–0.82B (all in at. %) cycled in strain control were experimentally studied. Hysteresis loop area, the cyclic hardening curves, the cyclic stress-strain curve and VH parameter were measured. Surface relief of cyclically strained specimens was observed using scanning electron microscopy. The variations of the VH parameter indicate the cyclic slip localization. The localization has a pronounced effect on surface relief formation. Persistent slip markings are formed on the surface along interlamellar interfaces gamma/aplha2 and gamma/gamma. These locations were nuclei for fatigue cracks in the interior of grains. Experimental results concerning the loop shape parameter and surface relief are used to discuss the role of cyclic slip localization on the cyclic stress-strain response and fatigue crack initiation.
Trvalý link: http://hdl.handle.net/11104/0225976