ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Isothermal low cycle fatigue (LCF) behaviours of a third generation titaniumaluminide based γ-TiAl alloy with duplex microstructure were investigated under the varioustest conditions, including temperature (550°C-750°C), total strain amplitude (0.3%-0.6%) andenvironment (air and vacuum), in order to clarify the fatigue life, deformation characters andfracture process of the alloy during LCF. The plastic strain accumulation has a greatcontribution to LCF damage. With increasing total strain range, LCF life decreases distinctly.Under the small total strain amplitude (≤0.4%), the increase of test temperature enforcesmicrostructure resistance to LCF fracture. However, the increase of test temperature togetherwith large total strain amplitude (〉0.5%) accelerates the microstructural degradation, whichbehaves the dissolution of α2 lamellae and recrystallization of γ phase, resulting in great LCFdamage. Moreover, environment brittlement during high temperature exposure to airinfluences the initiation process of fatigue cracks. The fracture mechanisms at various testconditions were analyzed
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/15/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.539-543.1571.pdf
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