Microstructure in Ti-48at.%Al PST crystal subjected to creep deformation

被引：12

作者：

Asai, T ^{[1
]}

Hirata, S ^{[1
]}

Takeyama, M ^{[1
]}

Matsuo, T ^{[1
]}

机构：

[1] Tokyo Inst Technol, Dept Met & Ceram Sci, Meguro Ku, Tokyo 1528552, Japan

来源：

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING | 2002年 / 329卷

基金：

日本学术振兴会;

关键词：

creep; fully transformed lamellar; PST crystal; orientation of alpha(2) plate to stress axis; TiAl alloy; accelerarating of creep rate;

D O I：

10.1016/S0921-5093(01)01635-5

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Tensile creep tests of the Ti-48at.%Al PST crystals with different lamellar orientation angles with respect to the stress axis phi were conducted at 1148 K and 68.6 MPa and the phi dependence of creep rate was investigated. The creep rate of the PST crystal strongly depends on phi. The minimum creep rate of the PST crystal with phi = 63degrees is three orders of magnitude larger than that of the PST crystal with phi = 3degrees, and the rupture life of the PST crystal with phi = 63degrees is one-tenth of that of the PST crystal with phi = 3degrees. The marked differences in creep rate and rupture life between the PST crystal with phi = 63degrees and that with phi = 3 would be ascribed to the role of alpha(2) plate to the operative slip systems. To confirm the above supposition, creep interruption tests in the wide strain range were conducted for the PST crystal with phi = 63degrees. The microstructure of the creep interrupted specimens gives the evidence to understand the role of alpha(2) plate to creep property, that is, the evolution of subgrain occurs just after collapsing of the alpha(2) plates, and the collapse of the alpha(2) plates directly coincides with the onset of accelerating creep. (C) 2002 Elsevier Science B.V. All rights reserved.

引用

页码：828 / 834

页数：7

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