The effect of nickel on the strength of iron nickel alloys: Implications for the Earth’s inner core
- Resource Type
- Authors
- Wendy L. Mao; Jin Liu; James A. Van Orman; Mary M. Reagan; A. E. Gleason; Michael J. Krawczynski
- Source
- Physics of the Earth and Planetary Interiors. 283:43-47
- Subject
- Dislocation creep
Materials science
010504 meteorology & atmospheric sciences
Physics and Astronomy (miscellaneous)
Scattering
Alloy
Inner core
chemistry.chemical_element
Astronomy and Astrophysics
engineering.material
010502 geochemistry & geophysics
01 natural sciences
Nickel
Geophysics
chemistry
Space and Planetary Science
engineering
Shear strength
Composite material
Deformation (engineering)
Earth (classical element)
0105 earth and related environmental sciences
- Language
- ISSN
- 0031-9201
We investigated the effect of nickel on the strength of iron-nickel (FeNi) alloys at high pressure. Using radial X-ray diffraction coupled with literature results from nuclear resonance inelastic X-ray scattering measurements we determined the bulk strength of two FeNi alloys (Fe0.88Ni0.12 and Fe0.8Ni0.2) at high pressures up to 70 GPa. When extrapolated to Earth’s inner core conditions, the strength of these FeNi alloys is found to increase relative to pure Fe. For the likely composition and conditions of the inner core, we estimate that an FeNi alloy with ∼5.5 wt% Ni would have a strength that is ∼125% greater than estimates for pure Fe. As shear strength is a measure of a material’s resistance to flow, our results have implications for understanding the deformation processes inside planetary interiors and support dislocation creep as the dominant mechanism in the Earth’s inner core.