Deformation and damage mechanisms during thermal-mechanical fatigue of a single-crystal superalloy
2009 (English)In: ACTA MATERIALIA, ISSN 1359-6454 , Vol. 57, no 7, 2266-2276 p.Article in journal (Refereed) Published
The deformation and damage mechanisms arising during thermal mechanical fatigue (TMF) of the single-crystal superalloy CMSX-4 have been investigated, both in the virgin condition and after long-term exposure at 1000 degrees C. Fundamental differences in the mechanical response due to ageing have been discovered, which are attributed to the tendency for the precipitation of topologically close-packed phases during deformation. In the virgin condition, the deformation during TMF is very localized and concentrated to twin bands which extend over the complete cross-section of the specimen; at the interception of these bands, the material is prone to recrystallization. The aged material on the other hand shows a much more dispersed deformation behaviour in which the length and thickness of the twins are much smaller and no recrystallization is found. Instead, significant local misorientations-implying crystal rotation are observed in the aged material after rupture.
Place, publisher, year, edition, pages
2009. Vol. 57, no 7, 2266-2276 p.
Thermal mechanical fatigue, Deformation mechanisms, Twinning, Recrystallization, Single crystal superalloy
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-18160DOI: 10.1016/j.actamat.2009.01.027OAI: oai:DiVA.org:liu-18160DiVA: diva2:216497