Study of nanometer-scaled lamellar microstructure in a Ti-45Al-7.5Nb alloy - Experiments and modeling

被引：22

作者：

Fischer, F. D. ^{[1
]}

Waitz, T. ^{[2
]}

Schen, Ch. ^{[3
]}

Cha, L. ^{[4
]}

Dehm, G. ^{[5
,6
]}

Antretter, T. ^{[1
]}

Clemens, H. ^{[4
]}

机构：

[1] Montanuniv, Inst Mech, A-8700 Leoben, Austria

[2] Univ Vienna, A-1090 Vienna, Austria

[3] Univ Munich, Dept Chem & Biochem, D-81377 Munich, Germany

[4] Montanuniv, Dept Met & Mat Testing, A-8700 Leoben, Austria

[5] Austrian Acad Sci, Erich Schmidt Inst Mat Sci, A-8700 Leoben, Austria

[6] Montanuniv, Dept Mat Phys, A-8700 Leoben, Austria

来源：

INTERMETALLICS | 2010年 / 18卷 / 04期

基金：

奥地利科学基金会;

关键词：

Titanium aluminides; Phase transformation; Thermal treatment; Microstructure; Modeling; PHASE-TRANSFORMATIONS; MECHANICAL TWINS; GAMMA; STRESS; ENERGY; DEFORMATION; COHERENCY; KINETICS; METALS; CREEP;

D O I：

10.1016/j.intermet.2009.09.012

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：

Quenching of Ti-45 at%Al-7.5 at%Nb from the single alpha-phase region to room temperature followed by aging below the eutectoid temperature leads to the precipitation of ultra-fine gamma-TiAl lamellae. In addition to an extensive experimental program, reported by Cha et al. in Intermetallics 16 (2008) 868-875, in this work a micromechanical and thermodynamical model is presented for the formation of gamma-TiAl lamellae within the alpha(2)-Ti3Al parent phase. A global transformation condition allows to predict a thickness to length ratio in accordance with experimental observations. Furthermore, a local transformation condition offers the basis for a kinetic law. The modeling concept can be applied to similar problems of combined diffusive and displacive phase transformations. (C) 2009 Elsevier Ltd. All rights reserved.

引用

页码：509 / 517

页数：9

共 48 条

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