The Kinetics of Precipitate Dissolution in a Nickel-Base Superalloy

The current literature reports the quantitative analysis of the kinetics of grain growth influenced by second-phase particle mechanisms for a powder metallurgy nickel-base superalloy: APK-6. Annealing treatments in the superalloy are shown to involve coarsening/dissolution of γ’ particles, and these particles mechanisms are shown to influence the kinetics of grain growth. The grain-growth exponent, n, is computed, and the γ’-solvus temperature of the superalloy is determined to lie between 220 and 270 oC. The kinetic data is interpreted to establish dependence of γ’ particles coarsening/dissolution mechanisms, grain size, γ’-solvus temperature, and annealing time and temperature on the rates of grain growth in the superalloy.

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Interaction of the Precipitation Kinetics of δ And γ’ Phases in Nickel-Base Superalloy ATI Allvac® 718PlusTM

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.2712 ◽

2010 ◽

Vol 638-642 ◽

pp. 2712-2717 ◽

Cited By ~ 8

Author(s):

Rene Radis ◽

Gerald A. Zickler ◽

Martin Stockinger ◽

Christof Sommitsch ◽

Ernst Kozeschnik

Keyword(s):

Volume Fraction ◽

Diffuse Interface ◽

Nickel Base Superalloy ◽

Interfacial Energies ◽

Precipitation Behaviour ◽

Planar Phase ◽

Nickel Base ◽

Kinetics Of ◽

Entropic Effects ◽

Base Superalloy

In this paper, the precipitation behaviour of  (Ni3(Nb,Al)) and ’ (Ni3(Al,Ti,Nb)) phases in the nickel-base superalloy ATI Allvac® 718PlusTM, as well as their kinetic interactions are discussed. Important parameters such as volume fraction, mean radius and number density of precipitates are experimentally determined and numerically simulated as a function of the heat treatment parameters time and temperature. To match the experimentally observed kinetics, the predicted interfacial energy of the precipitates, as calculated for a sharp, planar phase boundary, is adjusted to take into account the interfacial curvature and entropic effects of a diffuse interface. Correction functions for the interfacial energies of  as well as ’ precipitates are presented. Using these modified interfacial energies, the calculated results show excellent agreement with the experimental measurements.

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The Kinetics of the γ' Phase and Its Strain in the Nickel Base Superalloy SC16 Studied by In-Situ Neutron and Synchrotron Radiation Diffraction

Superalloys 2004 (Tenth International Symposium) ◽

10.7449/2004/superalloys_2004_837_846 ◽

2004 ◽

Author(s):

G. Bruno ◽

H.C. Pinto

Keyword(s):

Synchrotron Radiation ◽

Nickel Base Superalloy ◽

Synchrotron Radiation Diffraction ◽

Nickel Base ◽

Kinetics Of ◽

Base Superalloy

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Dissolution and precipitation kinetics of γ' in nickel base superalloy Udimet 520

Materials Science and Technology ◽

10.1179/026708302225001606 ◽

2002 ◽

Vol 18 (4) ◽

pp. 458-462 ◽

Cited By ~ 19

Author(s):

M. Jahazi ◽

A. R. Mashreghi

Keyword(s):

Nickel Base Superalloy ◽

Precipitation Kinetics ◽

Nickel Base ◽

Kinetics Of ◽

Dissolution And Precipitation ◽

Base Superalloy

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Dependence of Intergranular Fracture on Boundary Topography and Cohesion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071193 ◽

1973 ◽

Vol 31 ◽

pp. 150-151

Author(s):

J. E. Doherty ◽

A. F. Giamei ◽

B. H. Kear ◽

C. W. Steinke

Keyword(s):

Grain Boundary ◽

Room Temperature ◽

Nickel Base Superalloy ◽

Boundary Shear ◽

Room Temperature Ductility ◽

Solid Solution Matrix ◽

Nickel Base ◽

Solution Matrix ◽

Different Levels ◽

Base Superalloy

Recently we have been investigating a class of nickel-base superalloys which possess substantial room temperature ductility. This improvement in ductility is directly related to improvements in grain boundary strength due to increased boundary cohesion through control of detrimental impurities and improved boundary shear strength by controlled grain boundary micros true tures.For these investigations an experimental nickel-base superalloy was doped with different levels of sulphur impurity. The micros tructure after a heat treatment of 1360°C for 2 hr, 1200°C for 16 hr consists of coherent precipitates of γ’ Ni3(Al,X) in a nickel solid solution matrix.

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