Effect of order in Ti3Al particles and of temperature on the deformation behavior of age-hardened TiAl alloys

Gysler, A.; Weissmann, S.

doi:10.1016/0025-5416(77)90169-0

Cited by 41 publications

(16 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For an age-hardened TiAl alloy, the transition temperature was reported to be as low as 300 ЊC. [30] In IMI 834, however, this transition takes place well above 600 ЊC, as planar slip was obvious in all samples fatigued up to 600 ЊC (Figures 6(a) and 8(a)). These observations are supported in other studies, [8] where IMI 834 was fatigued at 500 ЊC and planar slip bands were found in both the primary ␣ grains and the lamellar regions.…”

Section: Fatigue Tests With a Maximum Temperature Of 650 њCmentioning

confidence: 98%

“…The formation of these slip bands is generally attributed to the shearing of ordered coherent Ti 3 Al precipitations by gliding dislocations. [8,30,31] Ti 3 Al precipitates can be easily identified, as these cause superlattice reflections in selected area diffraction (SAD) patterns. [32] Such superlattice reflections were observed in all SAD patterns obtained from primary ␣ grains, indicating that Ti 3 Al precipitates were indeed present in primary ␣ grains in all samples independent of test temperature.…”

Section: B Thermomechanical Fatigue Behaviormentioning

confidence: 99%

“…The tendency to a more planar type of dislocation slip results from the rather large difference in critical resolved stress (CRSS) between the individual slip systems. [30] Within the primary ␣ grains, planar slip is most evident, as shearing of the Ti 3 Al precipitates further promotes the formation of planar slip bands. Initially, shearing of the ordered Ti 3 Al causes cyclic softening.…”

Section: Comparison Ofmentioning

confidence: 99%

See 2 more Smart Citations

Thermomechanical fatigue behavior of the high-temperature titanium alloy IMI 834

Pototzky

Maier

Christ

1998

Metall Mater Trans A

View full text Add to dashboard Cite

The isothermal and thermomechanical fatigue (TMF) behavior of the titanium alloy IMI 834 was studied between 350 ЊC and 650 ЊC in air and vacuum, respectively. Transmission electron microscopy (TEM) observations revealed that the microstructure established in the TMF tests was governed by the maximum temperature within the cycle. However, if the maximum temperature does not exceed 600 ЊC, planar dislocation slip prevails and similar microstructures are formed regardless of the test temperature and the testing mode (TMF and isothermal, respectively). As a result, the stressstrain response in TMF tests can be assessed from the corresponding isothermal data. Wavy dislocation slip was found to determine the stress-strain behavior if the maximum test temperature exceeded 600 ЊC. Moreover, in TMF tests with a maximum test temperature of 650 ЊC, the dislocation arrangement formed in the high-temperature part of the hysteresis loop was found to be stable throughout the cycle and to affect significantly the stress-strain response at the low temperatures. Although in-phase (IP) and out-of-phase (OP) TMF tests led to an almost identical microstructure, OP loading was always found to be most detrimental. The interaction between the embrittled subsurface layer, caused by oxygen uptake, and the high tensile stresses developing in the low-temperature part of the hysteresis loop in OP tests eases crack initiation and initial crack propagation and results in reduced fatigue life.

show abstract

Section: Fatigue Tests With a Maximum Temperature Of 650 њCmentioning

confidence: 98%

Section: B Thermomechanical Fatigue Behaviormentioning

confidence: 99%

Section: Comparison Ofmentioning

confidence: 99%

See 1 more Smart Citation

Thermomechanical fatigue behavior of the high-temperature titanium alloy IMI 834

Pototzky

Maier

Christ

1998

Metall Mater Trans A

View full text Add to dashboard Cite

show abstract

“…3,11) When the coherent 2 particles are cut by the moving dislocations in the aged condition, their strengthening effect is reduced. The active slip plane is weakened and subsequent slip will occur on this slip plane preferentially, 9,11) which makes the width of the individual slip band decreased and the spacing between the adjacent slip bands increased, viz. the intensity of slip bands decreased in the aged specimens ( Fig.…”

Section: Discussionmentioning

confidence: 99%

“…For near-titanium alloys, depending on alloy composition, aging may result in the precipitation of incoherent silicide and coherent 2 phase based on Ti 3 Al, as well as the breaking-up of interplatelet films. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] These microstructrual changes will, in turn, lead to a decrease in ductility and a certain extent of gain in strength. [2][3][4][5] The aging treatment may also affect the creep and low cycle fatigue (LCF) properties in a complicated way.…”

Section: Introductionmentioning

confidence: 99%

Effect of Aging on Fatigue-Crack Growth Behavior of a High-Temperature Titanium Alloy

Liu

et al. 2004

Mater. Trans.

View full text Add to dashboard Cite

The effects of aging on the room-temperature fatigue-crack growth (FCG) behavior of a newly developed high-temperature neartitanium alloy (Ti-5.6Al-4.8Sn-2Zr-1.0Mo-0.32Si-0.8Nd) with both bimodal and lamellar microstructures were investigated. The results indicate that aging had a relatively small effect on the FCG behaviors of the concerned alloy. The effect of aging is more pronounced on the lamellar than on the bimodal microstructure. This effect reduces with aging time especially for the lamellar microstructure. TEM and SEM studies were performed to gain insight into the deformation behavior and crack propagation mechanisms of the alloy. Dependence of the FCG rates on aging treatment is rationalized by considering changes in crack path tortuosity, roughness-induced crack closure and deformation uniformity. Slip reversibility is also considered. The work suggests that the amount and size of 2 particles based on Ti 3 Al is mainly responsible for this dependence in the high ÁK range.

show abstract

Influence of test temperature and microstructure on the tensile properties of titanium alloys

Gysler

Lütjering

1982

Metall Trans A

View full text Add to dashboard Cite

Effect of order in Ti3Al particles and of temperature on the deformation behavior of age-hardened TiAl alloys

Cited by 41 publications

References 8 publications

Thermomechanical fatigue behavior of the high-temperature titanium alloy IMI 834

Thermomechanical fatigue behavior of the high-temperature titanium alloy IMI 834

Effect of Aging on Fatigue-Crack Growth Behavior of a High-Temperature Titanium Alloy

Influence of test temperature and microstructure on the tensile properties of titanium alloys

Contact Info

Product

Resources

About