Microscopic phase-field study on order-disorder transition of the antiphase domain boundary formed between L12 phases

Kinetics of order-disorder transition at antiphase domain boundary (APDB) formed between DO22 (Ni3V) phases during stress aging was investigated using microscopic phase field model. The results demonstrated that whether order-disorder transition happens or not depends on the atomic structure of the APDB. Accompanied with the depletion of V and enrichment of Ni and Al, order-disorder transition happened at the APDB (001)//(002). Whereas at the APDB {100}·1⁄2[100], which remains ordered with temporal evolution, Ni and Al enrich and V depletes. Composition evolution of APDB with order-disorder transition favors the nucleation of the L12 and disordered phase. Some of the grains grew bigger while the others disappeared, accompanying the formation of disordered phase layer during order-disorder transition of APDBs, and the order-disorder transition of APDBs can be considered as accompanying process of coarsening of ordered domain phases and growth of disordered phases.

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The partitioning behavior of dual solutes at the antiphase domain boundary in the B2 intermetallic: A microscopic phase-field study

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2020.153923 ◽

2020 ◽

Vol 824 ◽

pp. 153923

Author(s):

Kun Wang ◽

Yongxin Wang

Keyword(s):

Field Study ◽

Phase Field ◽

Domain Boundary ◽

Antiphase Domain ◽

Partitioning Behavior

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Kinetics of Order-Disorder Transition of Antiphase Domain Boundary Formed between DO22 Phases: Microscopic Phase-Field Study

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.996 ◽

2010 ◽

Vol 160-162 ◽

pp. 996-1000

Author(s):

Ming Yi Zhang ◽

Kun Yang ◽

Zheng Chen

Keyword(s):

Phase Field ◽

Domain Boundary ◽

Phase Field Model ◽

Antiphase Domain ◽

Precipitation Process ◽

Second Phase ◽

Phase Layer ◽

Disorder Transition ◽

Disordered Phase ◽

Kinetics Of

Based on the microscopic phase-field model, the precipitation process of Ni75Al4.3V20.7 alloy at 1190K is simulated, and the kinetics of order-disorder transition at antiphase domain boundary (APDB) formed between DO22 (Ni3V) phases is investigated. After the ordered APDB formed by the impingement of growing DO22 (Ni3V) domains, the order-disorder transition at APDB is happened. Accompanied with the enrichment of Ni and Al at the APDB, the ordered APDB transforms into a thin disordered phase layer. The second phase L12 nucleates at the order-disorder interface between DO22 and disordered phases, and grows along the disorder phase layer quickly. The order-disorder transition at the ordered APDB accelerates the nucleation and growth of L12 phase at the APDB. The disordered phase caused by the order-disordered transition can be considered the transient phase during the precipitation process of L12 phase.

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Microscopic Phase-Field Simulation of the Order-Disorder Transition of Antiphase Domian Boundary Formed between DO22 Phases

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.44-47.3736 ◽

2010 ◽

Vol 44-47 ◽

pp. 3736-3740

Author(s):

Ming Yi Zhang ◽

Kun Yang ◽

Zheng Chen

Keyword(s):

Phase Field ◽

Domain Boundary ◽

Phase Field Model ◽

Antiphase Domain ◽

Precipitation Process ◽

Second Phase ◽

Phase Layer ◽

Disorder Transition ◽

Disordered Phase ◽

Microscopic Phase Field Model

The order-disorder transition at antiphase domain boundary (APDB) between DO22 (Ni3V) phases is investigated using the microscopic phase-field model. After the formation of ordered APDB, the order-disorder transition at APDB is happened, and the ordered APDB transforms into a thin disordered phase layer. Accompanied with the enrichment of Ni and Al at the disordered APDB, the second phase L12 nucleates at the order-disorder interface between DO22 phases and grows along the disordered phase layer. The order-disorder transition at the ordered APDB makes the nucleation and growth of the second phase L12 much easier and faster. The disordered phase caused by the order-disorder transition at the APDB can be considered as the transient phase during the precipitation process of L12 phase.

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STRUCTURE OF Cu-Au ALLOY NANOSCALE PARTICLES AND THE PHASE TRANSFORMATION

Surface Review and Letters ◽

10.1142/s0218625x96000152 ◽

1996 ◽

Vol 03 (01) ◽

pp. 65-69 ◽

Cited By ~ 12

Author(s):

T. TADAKI ◽

A. KOREEDA ◽

Y. NAKATA ◽

T. KINOSHITA

Keyword(s):

Phase Transformation ◽

Domain Boundary ◽

High Resolution Electron Microscopy ◽

Antiphase Domain ◽

Minimum Size ◽

Nominal Composition ◽

Disorder Transition ◽

Nanoscale Particles ◽

Superlattice Structure ◽

Alloy Particles

Atomic structure of nanoscale particles of a Cu-Au alloy with a nominal composition Cu3Au and the phase transformation therein are studied by means of high-resolution electron microscopy and electron diffraction. The particles 8.8 nm in diameter on average prepared by simultaneous vacuum deposition of the constituent elements exhibit as a whole an fcc structure of an alloy with a composition of 26.4 at.% Au. The alloy particles are ordered into the L12-type superlattice structure when heat-treated at 563 K for 1 h. The superlattice reflections disappear upon heating up to 773 K. In a particle about 10 nm in size an antiphase domain boundary is observed. It thus appears that the nanoscale particles of the alloy undergo the order-disorder transition, as in the bulk. However, the critical temperature Tc for the order-disorder transition of the nanoscale particles is found to be by about 90 K lower than that of the bulk. The minimum size of the alloy particles in which lattice fringes whose spacing corresponds to the interplanar spacing of the {100}-type superlattice planes are observed is about 4 nm. These facts suggest that a certain critical size and size effects are present for atomic ordering in the Cu-Au alloy particles.

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