Computer simulation of morphological evolution and rafting of {gamma}{prime} particles in Ni-based superalloys under applied stresses

Journal Article · Sat Nov 01 04:00:00 EST 1997 · Scripta Materialia

DOI:https://doi.org/10.1016/S1359-6462(97)00276-5· OSTI ID:554031

Li, D Y; Chen, L Q ^[1]

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1. Pennsylvania State Univ., University Park, PA (United States). Dept. of Materials Science and Engineering

Mechanical properties of Ni-based superalloys are strongly affected by the morphology, distribution, and size of {gamma}{prime} precipitates in the {gamma} matrix. The main purpose of this paper is to propose a continuum field approach for modeling the morphology and rafting kinetics of coherent precipitates under applied stresses. This approach can be used to simulate the temporal evolution of arbitrary morphologies and microstructures without any a priori assumption. Recently, the authors applied this approach to the selected variant growth in Ni-Ti alloys under applied stresses using an inhomogeneous modulus approximation. For the {gamma}{prime} precipitates in Ni-based superalloys, the eigenstrain is dilatational, and hence the {gamma}{prime} morphological evolution can be affected by applied stresses only when the elastic modulus is inhomogeneous. In the present work, the elastic inhomogeneity was taken into account by reformulating a sharp-interface elasticity theory developed recently by Khachaturyan et al. in terms of diffuse interfaces. Although the present work is for a {gamma}{prime} {minus} {gamma} system, this model is general in a sense that it can be applied to other alloy systems containing coherent ordered intermetallic precipitates with elastic inhomogeneity.

• Sponsoring Organization: Office of Naval Research, Washington, DC (United States)
• OSTI ID: 554031
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 9 Vol. 37; ISSN 1359-6462; ISSN SCMAF7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPUTERIZED SIMULATION
DEFORMATION
ELASTICITY
FREE ENERGY
INTERFACES
INTERMETALLIC COMPOUNDS
KINETICS
LAMELLAE
MICROSTRUCTURE
MORPHOLOGY
NICKEL BASE ALLOYS
PARTICLE SIZE
PRECIPITATION
STRESSES