Cyclic behaviour of model Al–Li alloys: effect of the precipitate state
Małgorzata Lewandowska , Jarosław Mizera , J.W Wyrzykowski
AbstractThe effect of the precipitate state on the cyclic behaviour of model Al–Li alloys was investigated. The study has shown that the precipitate state has a significant effect on the low-cycle fatigue behaviour of the Al–Li alloys — on both the stress–response curve and dislocation structures. Al–Li alloys containing δ′ precipitates alone appear to undergo cyclic hardening, whereas an alloy with both δ′ and T1 precipitates shows a saturation state. Transmission electron microscopy on deformed samples shows that plastic deformation in Al–Li alloys is inhomogeneous. Microbands are present in the alloys that contain δ′ precipitates alone. An increase of the δ′ precipitate size leads to more pronounced strain localization. This has a detrimental effect on the fatigue life. The presence of T1 precipitates causes the plastic deformation to be more homogenous and improves the fatigue properties of the material. In this case, transmission electron microscopy examination reveals numerous dislocation loops formed during the fatigue test.
|Journal series||Materials Characterization, ISSN 1044-5803|
|Keywords in English||Al–Li alloy, Cyclic behaviour, Precipitate|
|ASJC Classification||; ; ;|
|Publication indicators||= 12; = 14; = 12.0; : 2000 = 0.319; : 2006 = 0.741 (2) - 2007=1.243 (5)|
|Citation count*||12 (2015-05-17)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.