Precipitate Redistribution during Creep of Alloy 617

被引：51

作者：

Schlegel, S. ^{[2
]}

Hopkins, S. ^{[1
]}

Young, E. ^{[1
]}

Cole, J. ^{[3
]}

Lillo, T. ^{[3
]}

Frary, M. ^{[1
]}

机构：

[1] Boise State Univ, Dept Mat Sci & Engn, Boise, ID 83725 USA

[2] ATI Wah Chang, Albany, OR 97321 USA

[3] Idaho Natl Lab, Dept Mat Sci & Engn, Idaho Falls, ID 83415 USA

来源：

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE | 2009年 / 40A卷 / 12期

基金：

美国能源部;

关键词：

GRAIN-BOUNDARY-CHARACTER; MICROSTRUCTURE; INCONEL-617; SUPERALLOY; BEHAVIOR; NICKEL; HELIUM;

D O I：

10.1007/s11661-009-0027-7

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Nickel-based superalloys are being considered for applications within advanced nuclear power generation systems due to their high-temperature strength and corrosion resistance. Alloy 617, a candidate for use in heat exchangers, derives its strength from both solid solution strengthening and the precipitation of carbide particles. However, during creep, carbides that are supposed to retard grain boundary motion are found to dissolve and reprecipitate on boundaries in tension. To quantify the redistribution, we have used electron backscatter diffraction (EBSD) and energy-dispersive spectroscopy (EDS) to analyze the microstructure of 617 after creep testing at 900 degrees C and 1000 degrees C. The data were analyzed with respect to the location of the carbides (e. g., intergranular vs intragranular), grain boundary character, and precipitate type (i.e., Cr rich or Mo rich). We find that grain boundary character is the most important factor in carbide distribution; some evidence of preferential distribution to boundaries in tension is also observed at higher applied stresses. Finally, the results suggest that the observed redistribution is due to the migration of carbides to the boundaries and not the migration of boundaries to the precipitates.

引用

页码：2812 / 2823

页数：12

共 26 条

[11] Correlation of grain-boundary precipitates parameters with fracture toughness in an Al-Cu-Mg-Ag alloy subjected to long-term thermal exposure [J].