Vortex-to-Polarization Phase Transformation Path in FerroelectricPb(ZrTi)O3Nanoparticles

Abstract Identifying structure phase transformation path is essential but challenging in plastic deformation under high-pressure high-strain rate experiments. In this paper, we adopt a framework based on non-equilibrium molecular dynamics and virtual diffraction to reproduce the phase transformation event observed in laser-driven ramp compression. Our simulation results reveal the detailed phase transformation pathway with atomic-level deformation physics while the simulated stress-density response and virtual diffraction patterns match the experimental observation with great accuracy.

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Alternative phase transformation path in cryogenically treated AISI D2 tool steel

Materials Science and Engineering A ◽

10.1016/j.msea.2015.03.028 ◽

2015 ◽

Vol 634 ◽

pp. 32-36 ◽

Cited By ~ 12

Author(s):

Hadi Ghasemi Nanesa ◽

Mohammad Jahazi

Keyword(s):

Phase Transformation ◽

Tool Steel ◽

Transformation Path ◽

Aisi D2 ◽

Aisi D2 Tool Steel

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Effect of ferrite-to-austenite phase transformation path on the interface crystallographic character distributions in a duplex stainless steel

Acta Materialia ◽

10.1016/j.actamat.2017.11.057 ◽

2018 ◽

Vol 145 ◽

pp. 196-209 ◽

Cited By ~ 31

Author(s):

N. Haghdadi ◽

P. Cizek ◽

P.D. Hodgson ◽

V. Tari ◽

G.S. Rohrer ◽

...

Keyword(s):

Stainless Steel ◽

Phase Transformation ◽

Duplex Stainless Steel ◽

Austenite Phase ◽

Transformation Path

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AB Initio Study of Changes in the Magnetism of Iron During the BCC-HCP Phase Transformation

MRS Proceedings ◽

10.1557/proc-538-523 ◽

1998 ◽

Vol 538 ◽

Cited By ~ 1

Author(s):

M. Šob ◽

M. Friák ◽

L.G. Wang ◽

V. Vitek

Keyword(s):

Phase Transformation ◽

Ab Initio ◽

High Precision ◽

Ab Initio Study ◽

Generalized Gradient ◽

Parameter Transformation ◽

Transformation Path ◽

Generalized Gradient Approximation ◽

Ferromagnetic Structure ◽

Spin Polarized

AbstractThe pressure-induced bcc-hcp transformation in iron is studied ab initio by following a constant-volume one-parameter transformation path. The calculations are performed in the generalized gradient approximation (GGA). It is shown that the analysis of both spin-polarized and non-spin-polarized states is essential in order to correctly obtain the energetics of the phase transformation. Our calculations make it possible to locate, with high precision, the transition configuration at which the bcc ferromagnetic structure transforms into the hcp nonmagnetic structure.

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Phase Transformation In Ti-6al-4v Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096175 ◽

1972 ◽

Vol 30 ◽

pp. 584-585

Author(s):

Shiro Fujishiro

Keyword(s):

Phase Transformation ◽

Grain Boundary ◽

Cryogenic Temperature ◽

Β Phase ◽

Heat Treated ◽

Mixed Microstructure ◽

Ductile Behavior

The Ti-6 wt.% Al-4 wt.% V commercial alloys have exhibited an improved formability at cryogenic temperature when the alloys were heat-treated prior to the tests. The author was interested in further investigating this unusual ductile behavior which may be associated with the strain-induced transformation or twinning of the a phase, enhanced at lower temperatures. The starting materials, supplied by RMI Co., Niles, Ohio were rolled mill products in the form of 40 mil sheets. The microstructure of the as-received materials contained mainly ellipsoidal α grains measuring between 1 and 5μ. The β phase formed an undefined grain boundary around the a grains. The specimens were homogenized at 1050°C for one hour, followed by aging at 500°C for two hours, and then quenched in water to produce the α/β mixed microstructure.

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Microstructural and Microchemical Characterization of Nickel Sulfide Inclusions in Plate Glass

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089123 ◽

1991 ◽

Vol 49 ◽

pp. 962-963

Author(s):

J. Cooper ◽

O. Popoola ◽

W. M. Kriven

Keyword(s):

Thermal Expansion ◽

Phase Transformation ◽

Glass Matrix ◽

Nickel Sulfide ◽

Plate Glass ◽

Thermal Expansion Mismatch ◽

Volume Increase ◽

Β Phase ◽

Microchemical Characterization

Nickel sulfide inclusions have been implicated in the spontaneous fracture of large windows of tempered plate glass. Two alternative explanations for the fracture-initiating behaviour of these inclusions have been proposed: (1) the volume increase which accompanies the α to β phase transformation in stoichiometric NiS, and (2) the thermal expansion mismatch between the nickel sulfide phases and the glass matrix. The microstructure and microchemistry of the small inclusions (80 to 250 μm spheres), needed to determine the cause of fracture, have not been well characterized hitherto. The aim of this communication is to report a detailed TEM and EDS study of the inclusions.

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AEM of reaction-bonded SiC

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122125 ◽

1992 ◽

Vol 50 (1) ◽

pp. 344-345

Author(s):

K Das Chowdhury ◽

R. W. Carpenter ◽

W. Braue

Keyword(s):

Mechanical Properties ◽

Phase Transformation ◽

High Temperature ◽

Epitaxial Growth ◽

Liquid Silicon ◽

Structural Ceramic ◽

Few Data

Research on reaction-bonded SiC (RBSiC) is aimed at developing a reliable structural ceramic with improved mechanical properties. The starting materials for RBSiC were Si,C and α-SiC powder. The formation of the complex microstructure of RBSiC involves (i) solution of carbon in liquid silicon, (ii) nucleation and epitaxial growth of secondary β-SiC on the original α-SiC grains followed by (iii) β>α-SiC phase transformation of newly formed SiC. Due to their coherent nature, epitaxial SiC/SiC interfaces are considered to be segregation-free and “strong” with respect to their effect on the mechanical properties of RBSiC. But the “weak” Si/SiC interface limits its use in high temperature situations. However, few data exist on the structure and chemistry of these interfaces. Microanalytical results obtained by parallel EELS and HREM imaging are reported here.

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