Dynamical stability of iron under high-temperature and high-pressure conditions

  title={Dynamical stability of iron under high-temperature and high-pressure conditions},
  author={Leilei Kong and J. Li and Qiang Shi and Hengye Huang and Kai Zhao},
  journal={EPL (Europhysics Letters)},
  • L. Kong, J. Li, K. Zhao
  • Published 1 March 2012
  • Materials Science, Physics
  • EPL (Europhysics Letters)
The dynamical stability of iron under high-temperature and high-pressure conditions was investigated based on the phonons evaluated by using a recently developed method. It is revealed that both the fcc-Fe and the hcp-Fe are dynamically stable in a wide temperature and pressure range. The bcc-Fe phase can be stable as well, while in a limited temperature/pressure regime bounded by a dynamical stability limit and a harmonic limit. Direct evidence shows that it is the entropy term that plays a… 

Dynamic stability of Fe under high pressure

We study the dynamic stability of bcc iron at both high pressure and temperature via Molecular Dynamics in conjunction with three different interatomic potentials constructed within the embedded-atom

Phase Transition of Iron-based Single Crystals at Extreme Strain Rates under Dynamic Loadings

Phase transition of iron, as a prototype of martensite phase transition under dynamic loadings, exhibits huge diverges in its TP among experiments with different pressure medium and loading rates,

The effect of pressure on the crystallization of rapidly supercooled zirconium melts.

Molecular dynamics simulations have been performed to explore the effect of pressure (P) on the crystallization of zirconium (Zr) under rapid cooling and reveal that if nucleation is essentially completed at the end of the first crystalline (bcc-dominated) stage, MisC will occur; otherwise, SisC occurs.

Experimental evidence of a body centered cubic iron at the Earth's core condition

The crystal structure of iron in the Earth's inner core remains debated. Most recent experiments suggest a hexagonal-close-packed (hcp) phase. In simulations, it has been generally agreed that the

Stability of iron crystal structures at 0.3–1.5 TPa

The role of chromium and nickel on the thermal and mechanical properties of FeNiCr austenitic stainless steels under high pressure and temperature: a molecular dynamics study

ABSTRACT The effect of Cr and Ni content on thermo-mechanical properties of FeNiCr austenitic stainless steel under ambient and high pressure and temperature were investigated by MD simulations. The



Importance of shear in the bcc-to-hcp transformation in iron.

A multiscale model containing a quantum-mechanics-based multiwell energy function accounting for the bcc and hcp phases of Fe and a construction of kinematically compatible and equilibrated mixed phases suggests that shear stresses have a significant influence on the bCC<-->hcp transformation.

Shock temperatures and melting of iron at Earth core conditions.

The temperature of shock compressed iron has been measured to 340 GPa, using well characterized iron films sputtered on transparent diamond substrates and a 1 ns time-resolved optical method. We find

Crystal instabilities at finite strain.

It is demonstrated that stability criteria derived using elastic stiffness coefficients which govern stress-strain relations at finite deformation give quantitative predictions of crystal

Where is the supercritical fluid on the phase diagram?

We discuss the fluid state of matter at high temperature and pressure. We review the existing ways in which the boundary between a liquid and a quasigas fluid above the critical point are discussed.

Dynamical Theory of Crystal Lattices

Although Born and Huang's classic work on the dynamics of crystal lattices was published over thirty years ago, the book remains the definitive treatment of the subject. It begins with a brief

Large-scale Atomic/Molecular Massively Parallel Simulator

(LAMMPS) was used to obtain atomistic insights in slip mechanisms , their dependence on crystal orientation, and the differences in the frictional behavior between low stacking fault energy

Quantitative results for square gradient models of fluids

Square gradient models for fluids are extensively used because they are believed to provide a good qualitative understanding of the essential physics. However, unlike elasticity theory for solids,

Introduction to Lattice Dynamics

Foreword Acknowledgements Definitions of symbols used 1. Some fundamentals 2. The harmonic approximation and lattice dynamics of very simple systems 3. Dynamics of diatomic crystals: general