Transition-metal alloying of γ′−Ni3Al: Effects on the ideal uniaxial compressive strength from first-principles calculations

The addition of transition-metal (TM) elements into the γ′ precipitate phase of a Ni-based single-crystal superalloy can significantly affect its mechanical properties, including the intrinsic mechanical property of compressive strength. Using first-principles density functional calculations, the ef...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B 2018-01, Vol.97 (2)
Main Authors: Wen, Minru, Wang, Chong-Yu
Format: Article
Language:English
Subjects:
Alloy development
Alloying effects
Alloying elements
Cadmium
Chromium
Compressive strength
Deformation mechanisms
Density functional theory
First principles
Hafnium base alloys
Intermetallic compounds
Intermetallic phases
Mathematical analysis
Mechanical properties
Molybdenum
Nickel aluminides
Nickel base alloys
Single crystals
Strain analysis
Stress-strain relationships
Superalloys
Transition metal alloys
Transition metals
Tungsten
Yttrium
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The addition of transition-metal (TM) elements into the γ′ precipitate phase of a Ni-based single-crystal superalloy can significantly affect its mechanical properties, including the intrinsic mechanical property of compressive strength. Using first-principles density functional calculations, the effects of 3d (Sc-Zn), 4d (Y-Cd), and 5d (Hf-Au) TM alloying elements on the ideal uniaxial compressive strength of γ′−Ni3Al were investigated. The stress-strain relationships of pure Ni3Al under [100], [110], and [111] compressive loads and the site occupancy behavior of TM elements in Ni3Al were previously studied using a total-energy method based on density functional theory. Our results showed that the capacity of TM elements for strengthening the ideal compressive strength was associated with the d-electron number. The alloying elements with half-filled d bands (i.e., Cr, Mo, W, Tc, and Re) manifested the greatest efficacy for improving the ideal strength of Ni3Al under a deformation along the weakest compressive direction. Furthermore, the charge redistribution of Ni3Al doped with 5d elements were also analyzed to understand the strengthening mechanisms of TM elements in the γ′−Ni3Al phase.
ISSN:2469-9950
2469-9969
DOI:10.1103/PhysRevB.97.024101