Strain aging embrittlement of the ordered intermetallic compound NiAl

Ti3Al is an ordered intermetallic compound having the DO19-type superlattice structure. The compound exhibits very limited ductility in tension below 700°C because of a pronounced planarity of slip and the absence of a sufficient number of independent slip systems. Significant differences in slip behavior in the compound as a result of differences in strain rate and mode of deformation are reported here.Figure 1 is a comparison of dislocation substructures in polycrystalline Ti3Al specimens deformed in tension, creep, and fatigue. Slip activity on both the basal and prism planes is observed for each mode of deformation. The dominant slip vector in unidirectional deformation is the a-type (b) = <1120>) (Fig. la). The dislocations are straight, occur for the most part in a screw orientation, and are arranged in planar bands. In contrast, the dislocation distribution in specimens crept at 700°C (Fig. lb) is characterized by a much reduced planarity of slip, a tangled dislocation arrangement instead of planar bands, and an increased incidence of nonbasal slip vectors.

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Single-Phase Interdiffusion in Intermetallic Compound NiAl

Journal of the Japan Institute of Metals and Materials ◽

10.2320/jinstmet1952.62.8_761 ◽

1998 ◽

Vol 62 (8) ◽

pp. 761-765 ◽

Cited By ~ 5

Author(s):

Masahiko Kato ◽

Hisaoki Sasano ◽

Kazuhiro Honma ◽

Toshiyuki Suzuki

Keyword(s):

Intermetallic Compound ◽

Single Phase ◽

Intermetallic Compound Nial

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In situ investigations on the oxidation of the ordered intermetallic compound Co0.6Ga0.4

Solid State Ionics ◽

10.1016/s0167-2738(00)00558-0 ◽

2000 ◽

Vol 136-137 (1-2) ◽

pp. 971-977 ◽

Cited By ~ 2

Author(s):

U Koops

Keyword(s):

Intermetallic Compound ◽

Ordered Intermetallic

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VOIDS IN THE INTERMETALLIC COMPOUND NiAl.

VOIDS FORMED BY IRRADIATION OF REACTOR MATERIALS ◽

10.1680/vfbiorm.44623.0014 ◽

1969 ◽

pp. 177-182

Author(s):

H. L. Fraser ◽

M. H. Loretto ◽

R. E. Smallman ◽

R. J. Wasilewski

Keyword(s):

Intermetallic Compound ◽

Intermetallic Compound Nial

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Anelastic relaxation behavior of hydrogen in L12 ordered intermetallic compound Ni3Al

Scripta Materialia ◽

10.1016/s1359-6462(02)00256-7 ◽

2002 ◽

Vol 47 (9) ◽

pp. 625-629 ◽

Cited By ~ 3

Author(s):

C.B. Jiang ◽

H. Li ◽

C.X. Huang ◽

G.Y. Li ◽

S.D. Wu ◽

...

Keyword(s):

Intermetallic Compound ◽

Relaxation Behavior ◽

Ordered Intermetallic

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Effect of Ag on the Hot Corrosion of NiAl Intermetallic Compound

High Temperature Materials and Processes ◽

10.1515/htmp-2012-0150 ◽

2013 ◽

Vol 32 (4) ◽

pp. 359-365

Author(s):

S.N. Liu ◽

W. Su ◽

W.Y. Lv ◽

Z.F. Wei ◽

C.L. Zeng

Keyword(s):

Intermetallic Compound ◽

Hot Corrosion ◽

Weight Percent ◽

Typical Feature ◽

Localized Corrosion ◽

High Temperature Strength ◽

Physical Analysis ◽

Two Phase ◽

Analysis Techniques ◽

Intermetallic Compound Nial

AbstractThe low ambient tensile ductility and inadequate high temperature strength and creep resistance have limited the applications of intermetallic compound NiAl as a structure material at high temperatures. A small addition of Ag could increase the strength of NiAl. In this study, hot corrosion behavior of NiAl and NiAl-Ag containing 1 and 5%Ag (in weight percent), respectively, in molten (Na,K)2SO4 at 1173 K has been examined by thermogravimetry and physical analysis techniques. The experimental results indicated that the corrosion rates of NiAl and NiAl-Ag tended to increase with exposure time, accompanied with the formation of nodules. Fast localized corrosion is the typical feature of the corrosion of both NiAl and NiAl-Ag. The addition of Ag to NiAl accelerated its corrosion, with a higher corrosion rate observed for the 5%Ag addition. The two-phase microstructure of NiAl-Ag alloys accelerated the formation of nodules in the regions close to Ag phases.

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