The fracture behavior of recrystallized Al-2.8% Li-0.3% Mn sheet

Sanders, T. H.; Ludwiczak, E. A.; Sawtell, R. R.

doi:10.1016/0025-5416(80)90110-x

Cited by 100 publications

(21 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similarly, the transition from complete transgranular fracture to increasing amounts of intergranular fracture for lightly-aged 8090 (Lynch et al 1993) is difficult to explain, since the microstructure would not be expected to have changed sufficiently to have a significant effect on the fracture mechanism. This view is supported by the observation that grain boundaries in an Al-2.78wt% Li-0.32wt% Mn alloy were free from coarse precipitates after 1 week of natural ageing (Sanders et al 1980). …”

Section: Grain Boundary Precipitationmentioning

confidence: 81%

“…The occurrence of slip steps on smooth intergranular fracture regions has been considered as indirect evidence that slip planarity is responsible for brittle intergranular fracture (Sanders et al 1980). In the present study, slip steps were seen only rarely on the intergranular fracture surfaces but, when observed, were found to be present on ductile, as well as brittle, intergranular fracture surfaces.…”

Section: Slip Planaritymentioning

confidence: 99%

“…Slip traces on intergranular fracture surfaces have been taken as indicative of interaction between planar slip and grain boundaries (Sanders et al 1980) and the slip traces have generally been shown for smooth intergranular facets. Observation of fracture surfaces from the fracture toughness samples using optical microscopy and SEM showed that slip traces were rarely seen on the intergranular fracture surfaces and, when observed, were found to be present in both the brittle and ductile intergranular regions.…”

Section: Slipmentioning

confidence: 99%

See 2 more Smart Citations

A study aimed at determining and understanding the fracture behaviour of an Al–Li–Cu–Mg–Zr alloy 8090

Bregianos¹,

Crosky

Munroe

et al. 2010

Int J Fract

View full text Add to dashboard Cite

The S-L fracture toughness of aluminiumlithium based alloys is generally poor and this has limited their applicability, particularly in aerospace where good damage tolerance is required. The low S-L toughness has been attributed variously to grain boundary precipitation, planar slip and lithium segregation. This work examined the S-L fracture behaviour of an 8090 Al-Li-based alloy in 34-45 mm plate. The results confirmed that the S-L fracture toughness decreases from the centre to the surface of plate material and increases with double ageing. Fracture is principally intergranular, with both ductile and brittle components occurring, but some transgranular fracture also occurs and this produces steps in the fracture plane. Changes in the relative proportions of brittle and ductile intergranular fracture, as well as in the amount of transgranular fracture, accompany the changes in toughness. However, A. C. Bregianos the decrease in fracture toughness across the plate is accompanied principally by an increase in the relative proportion of brittle intergranular fracture, while the toughening produced by double ageing is accompanied principally by an increase in the amount of transgranular fracture. Evidence of coarse slip, indicative of slip planarity, was seen from slip steps and dislocation structures. However, planar slip was seen only towards the centre of the plate and not towards the surface. The level of planar slip was not reduced markedly by double ageing. Texture varied with position across the plate. There were also a larger number of low angle boundaries towards the centre of the plate than towards the surface. The hardness did not change across the plate. The results could not be explained fully in terms of either the grain boundary precipitate theory or the planar slip model, but were generally consistent with the lithium segregation model. However, the basic tenet of this model is that the level of embrittlement is influenced by the grain boundary structure, and the results did not indicate a substantial difference between the boundaries that failed in a ductile manner and those which failed by brittle fracture. This suggests that the factors which affect lithium segregation may be more complex than originally envisaged.Keywords Short transverse · S-L orientation · Fracture behaviour · Toughness · 8090 Aluminiumlithium based aerospace alloy 123 142 A. C. Bregianos et al.

show abstract

Section: Grain Boundary Precipitationmentioning

confidence: 81%

Section: Slip Planaritymentioning

confidence: 99%

Section: Slipmentioning

confidence: 99%

See 1 more Smart Citation

A study aimed at determining and understanding the fracture behaviour of an Al–Li–Cu–Mg–Zr alloy 8090

Bregianos¹,

Crosky

Munroe

et al. 2010

Int J Fract

View full text Add to dashboard Cite

show abstract

“…Since the effects of precipitate free zones(PFZ's) were first examined in high strength AI-Mg-Zn alloys [1,2] much attention has been paid to PFZ's and· their deleterious effects, especially with respect to the mechanical behaviour, fracture and stress-corrosion cracking, in a wide range of conventional high strength AI-base alloys [3][4][5][6][7][8][9], as well as in the newer high strength AI-Li alloys for aerospace applications [10][11][12][13][14]. In terms of complexities and mechanisms of precipitate nucleation and growth, including considerable non-uniformity due to heterogeneous nucleation, conventional Al base alloys are very similar to the AI-Li-base alloys.…”

Section: Introductionmentioning

confidence: 99%

“…by mechanical deformation as in the complex thermomechanical treatments (TMT) currently being pursued. The phenomenon of PFZ's in high strength AI-Li-base alloys has been extensively studied [10,11,15]. In order to establish the mechanism of formation of PFZ's, it is important to determine whether the PFZ's are a result of.…”

Section: Introductionmentioning

confidence: 99%

Lithium depletion in precipitate free zones (PFZ's) in AlLi base alloys

Radmilović

Fox

Fisher

et al. 1989

Scripta Metallurgica

View full text Add to dashboard Cite

Effect of heat treatments on 8090 AlLi alloy pitting susceptibility in sea water

Beccaria¹,

Traverso²

1996

Materials & Corrosion

View full text Add to dashboard Cite

The pitting susceptibility of 8090 Al-Li alloy in sea water, after different heat treatments, was investigated.Free corrosion and electrochemical tests were carried out at 2 5 T , in quiescent sea water at pH = 8.2 and dissolved oxygen = 6.5 ppm.The microstructure was examined by metallographic microscopy and by X-Ray microdiffractometry, while the corrosion layer was characterized by chemical methods and by Infrared and X-Ray photoelectron spectroscopies.The following was observed: 0 aging treatments lead to a non homogeneous microstructure which increases the average corrosion rate as well as pitting susceptibility; 0 heat treatments do not affect the average passive film composition; 0 in all examined states, A1-Li alloy 8090 is subject to localized corrosion which takes place preferentially at the grain boundaries.Die Lochkorrosionsempfindlichkeit der Legierung 8090 AI-Li in Meerwasser wurde nach verschiedenen Warmebehandlungen untersucht.Versuche bei freier Korrosion sowie eletrochemische Versuche wurden bei 25°C in nicht bewegtem Meerwasser mit pH 8,2 und einem Gehalt von 6,5 ppm gelostem Sauerstoff durchgefiihrt.Das Gefiige wurde mittels metallographischer Mikroskopie und Rontgenfeinstrukturanalyse untersucht, wahrend die Korrosionsschicht mit Hilfe von chemischen Methoden sowie Infrarot-und Rontgenphotoelektronenspektroskopie charakterisiert wurde.Folgendes wurde festgstellt: 0 Alterungsbehandlungen fiihren zu einem inhomogenen Gefiige, was sowohl die allgemeine Korrosionsgeschwindigkeit als auch die Lochkorrosionsempfindlichkeit erhoht, 0 Warmebehandlungen beeinflussen nicht die Zusammensetzung des Passivfilms, 0 in allen untersuchten Fallen ist die Al-Li-Legierung 8090 anfallig gegeniiber lokaler Korrosion, die bevorzugt an den Korngren-Zen stattfindet.

show abstract

The fracture behavior of recrystallized Al-2.8% Li-0.3% Mn sheet

Cited by 100 publications

References 4 publications

A study aimed at determining and understanding the fracture behaviour of an Al–Li–Cu–Mg–Zr alloy 8090

A study aimed at determining and understanding the fracture behaviour of an Al–Li–Cu–Mg–Zr alloy 8090

Lithium depletion in precipitate free zones (PFZ's) in AlLi base alloys

Effect of heat treatments on 8090 AlLi alloy pitting susceptibility in sea water

Contact Info

Product

Resources

About