Microstructural observations of as-prepared and thermal cycled NiCoCrAlY bond coats

被引：41

作者：

Mendis, B. G.

Tryon, B.

Pollock, T. M.

Hemker, K. J. ^{[1
]}

机构：

[1] Johns Hopkins Univ, Dept Mech Engn, Baltimore, MD USA

[2] Univ Michigan, Dept Mat Sci, Ann Arbor, MI 48109 USA

来源：

SURFACE & COATINGS TECHNOLOGY | 2006年 / 201卷 / 07期

关键词：

NiCoCrAlY bond coat; phase transitions; diffusion; transmission electron microscopy;

D O I：

10.1016/j.surfcoat.2006.07.249

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Microstructures of as-prepared and 1100 degrees C/100 h isothermally annealed NiCoCrAlY bond coat specimens as well as a bond coat obtained from an end of life turbine blade were characterized with TEM. In all specimens the gamma grains were observed to consist of fine gamma precipitates, which form during cooling and are unstable at the higher operating temperatures. The beta grains present in the as-prepared specimens were observed to transform to L1(0) martensite in the 1100 degrees C/100 h isothermally annealed specimen. As a result of substrate-bond coat interdiffusion the M-s temperature increases during thermal cycling due to an increase in Ni and decrease in the Cr concentrations of the beta-phase. The turbine blade bond coat was also found to contain Cr and Co-rich sigma-phase precipitates. (c) 2006 Elsevier B.V All rights reserved.

引用

页码：3918 / 3925

页数：8

共 22 条

[11] The influence of a martensitic phase transformation on stress development in thermal barrier coating systems [J].

Glynn, ML ;

Chen, MW ;

Ramesh, KT ;

Hemker, KJ .

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 2004, 35A (08) :2279-2286

[12]

HORNBOGEN E, 1967, Z METALLKD, V58, P842

[13] Effect of alloying elements on martensitic transformation in the binary NiAl(beta) phase alloys [J].

Kainuma, R ;

Ohtani, H ;

Ishida, K .

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 1996, 27 (09) :2445-2453

[14] Materials science - Thermal barrier coatings for gas-turbine engine applications [J].

Padture, NP ;

Gell, M ;

Jordan, EH .

SCIENCE, 2002, 296 (5566) :280-284

[15] The precipitation of topologically close-packed phases in rhenium-containing superalloys [J].

Rae, CMF ;

Reed, RC .

ACTA MATERIALIA, 2001, 49 (19) :4113-4125

[16] ANOMALIES IN ELECTRON-DIFFRACTION PATTERNS OF NICKEL-RICH BETA-'-NIAL ALLOYS [J].

REYNAUD, F .

SCRIPTA METALLURGICA, 1977, 11 (09) :765-770

[17] TWEED MICROSTRUCTURES .1. CHARACTERIZATION IN BETA-NIAL [J].

ROBERTSON, IM ;

WAYMAN, CM .

PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES, 1983, 48 (03) :421-442

[18]

ROWLAND LJ, 2005, THESIS U MICHIGAN

[19]

SAUNDERS N, 2000, NI DATA INFORM THERM

[20]

TRYON B, UNPUB

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