Tension/Compression asymmetry of a single-crystal superalloy in virgin and degraded condition
2010 (English)In: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 58, no 15, 4986-4997 p.Article in journal (Refereed) Published
The mechanical behaviour at room temperature of a single-crystal superalloy exposed to long term ageing at elevated temperature has been investigated, a topic important for the material’s resistance to thermal-mechanical fatigue. Specimens with several different crystallographic orientations were plastically deformed in either tension or compression before and after the long term furnace exposure. While the thermally activated degradation of the microstructure causes a reduction in yield limit of up to 25% for specimens initially deformed in the |001 and |011| directions, none or only moderate reduction was seen for specimens initially deformed along the |111| direction. This can be explained by the strong correlation between yield limit reduction and the amount of γ coarsening. By introducing an isotropic degradation function in a newly developed crystal plasticity model, the constitutive behaviour of both virgin and degraded materials has been described with good agreement with the experimental results.
Place, publisher, year, edition, pages
2010. Vol. 58, no 15, 4986-4997 p.
Deformation mechanisms, Rafting/Coarsening, Tension/compression asymmetry, Single-crystal superalloy
National CategoryEngineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-56590DOI: 10.1016/j.actamat.2010.05.032ISI: 000280570500008OAI: oai:DiVA.org:liu-56590DiVA: diva2:320532