Cryogenic mechanical properties of low density superplastic aluminum alloys

Verzasconi, S. L.

doi:10.2172/5855723

Cited by 4 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The marked increase in fracture toughness at low temperatures in sharp-notch tests is not observed in blunt notch tests. Verzasconi [1989] found that the tear/yield ratio measured in Kahn tear tests of specimens at T/2 was roughly the same at 77 K and 300 K; the UPE increased fairly substantially at 77 K over the 300 K value. Charpy tests of this material (L-T oriented specimen) yielded similar results; only a slight increase was observed.…”

Section: "T---•mentioning

confidence: 83%

“…An example of this phenomenon exists in the current study; the large increase in toughness at low temperature observed for 2090-T81 L-T is not seen in the corresponding Charpy impact specimens. Verzasconi [1989] found that the tear/yield ratio measured in a Kahn tear test did not change significantly from 300 to 77 K, although the UPE did increase somewhat. The discrepancy between the results of sharp notch and blunt notch tests is not limited to 2090.…”

Section: Influence Of Grain Shapementioning

confidence: 87%

“…The behavior of 2090 is a focus of this study and of other recent work; the possible mechanisms at work will be discussed in detail in later sections. The improvement is not simply due to the presence of lithium, since other aluminumlithium alloys do not show improvements as striking as those in 2090 [Glazer and Morris, 1989;Verzasconi, 1989].…”

Section: Fracture Toughnessmentioning

confidence: 99%

“…The properties of superplastic modifications of these alloys have also been studied Because the superplastic alloys have a fine equiaxed grain structure, their fracture behavior is different In sheet form, these alloys generally show an increase in tensile elongation but a decrease in fracture toughness with decreasing temperature [Glazer et al, 1988;Verzasconi, 1989].…”

Section: Superplastic Modificationsmentioning

confidence: 99%

“…A moderately large data base exists for this test; however, direct comparisons with data obtained at other laboratories is difficult because variations in machine compliance and control mode appear to have a large effect on the results, particularly on the UPE. The test specimens, procedures and comparability of tests are discussed in greater detail by Verzasconi [1989]. Because of the difficulty of obtaining samples of uniform processing from the headbox, only the unformed superplastic sheet was examined.…”

Section: Blunt Notch Testsmentioning

confidence: 99%

See 4 more Smart Citations

The strength-toughness combination of the aluminum-lithium alloys 2090 and 2091 at cryogenic temperatures

Glazer¹

1989

View full text Add to dashboard Cite

The strength-toughness combination of the aluminum-lithium alloys 2090 (nominal composition Al-2.7 Cu-2.2 Li-0.1 Zr in wt. %) and 2091 (Al-2.2 Cu-2.0 Li-1.5 Mg-0.1 Zr) plate at cryogenic temperatures was investigated. Aluminum-lithium alloys have lower density and higher stiffness than conventional aluminum alloys and were developed for aircraft applications. This study was motivated by the possibility of using aluminumlithium alloys for cryogenic tankage of spacecraft, an application in which light weight, weldability and good cryogenic mechanical properties are at a premium. Alloy 2090-T81 has a strength-toughness combination that improves with decreasing temperature between 300 and 4 K under some conditions. This improvement is accompanied by an increase in the tensile elongation and strain hardening rate, but the large increase in fracture toughness is not reflected in the primary fracture mode. The goal of this study was to develop an understanding of the mechanisms responsible for the increase in fracture toughness at cryogenic temperatures. The mechanical properties of alloy 2090 in other metallurgical conditions and a second alloy, 2091, were also considered.

show abstract

Section: "T---•mentioning

confidence: 83%

Section: Influence Of Grain Shapementioning

confidence: 87%

Section: Fracture Toughnessmentioning

confidence: 99%

Section: Superplastic Modificationsmentioning

confidence: 99%

Section: Blunt Notch Testsmentioning

confidence: 99%

See 3 more Smart Citations