Creep and microstructure of near-gamma TiAl alloys

被引：18

作者：

Dlouhy, A ^{[1
]}

Kucharová, K ^{[1
]}

机构：

[1] Acad Sci Czech Republ, Inst Phys Mat, Brno 61662, Czech Republic

来源：

INTERMETALLICS | 2004年 / 12卷 / 7-9期

关键词：

titanium aluminides; based on TiAl; creep; precipitates; microstructure; electron microscopy; transmission;

D O I：

10.1016/j.intermet.2004.03.007

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Creep strength and microstructure of Ti-48Al-2Cr-2Nb-1B and Ti-46Al-2W-0.5Si-(0.7B) alloys are compared. The influence of a prior-to-creep heat treatment on the initial microstructure is investigated. The isothermally forged and heat treated Ti-48Al-2Cr-2Nb-1B alloy was tested in nearly lamellar and equiaxed modifications while the cast and HIP-ped Ti-46Al-2W-0.5Si alloy was either nearly lamellar or duplex before creep. All these microstructural variants were crept in tension at 1023 K and at different applied stresses. Experimental results obtained in the present study suggest that, in spite of creep strength variations resulting from the different microstructural states, the Ti-46Al-2W-0.5Si alloy performs better than the Ti-48Al-2Cr-2Nb-1B alloy. Transmission electron microscopy analysis provided evidence that W- and Si-rich phases that precipitate both, on the lamellar boundaries and inside the gamma grains, contribute to the superior creep strength of the Ti-46Al-2W-0.5Si alloy. (C) 2004 Elsevier Ltd. All rights reserved.

引用

页码：705 / 711

页数：7

共 17 条

[1] Creep deformation in two-phase titanium aluminide alloys [J].

Appel, F ;

Christoph, U ;

Oehring, M .

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2002, 329 :780-787

[2]

Beddoes J, 1995, INT MATER REV, V40, P197, DOI 10.1179/095066095790151151

[3] Dislocation slip and deformation twinning interplay during high temperature deformation in γ-TiAl base intermetallics [J].

Dlouhy, A ;

Kucharová, K ;

Brezina, J .

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2001, 319 :820-826

[4] Microstructural evolution associated with creep rate minima in pure- and near-γ TiAl intermetallics [J].

Dlouhy, A ;

Kucharová, K ;

Horkel, T .

CREEP AND FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, 2000, 171-1 :693-700

[5]

DLOUHY A, 2001, MAT STRUCTURE MICROM, P240

[6]

DLOUHY A, 2002, MAT ADV POWER ENG 20, P605

[7]

DOBES F, 1986, J METAL MAT, V24, P599

[8]

HOSTINSKY T, 1976, J TEST EVAL, V4, P26, DOI 10.1520/JTE10503J

[9] AN IN-SITU OBSERVATION OF MECHANICAL TWIN NUCLEATION AND PROPAGATION IN TIAL [J].

JIN, Z ;

BIELER, TR .

PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES, 1995, 71 (05) :925-947

[10] Strength and ductility in TiAl alloys [J].

Kim, YW .

INTERMETALLICS, 1998, 6 (7-8) :623-628

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