Nucleation and Dendritic Growth in Undercooled Melts

1995 ◽  
Vol 398 ◽  
Author(s):  
Dieter M. Herlach
Keyword(s):  
Crystal Growth ◽  
Growth Velocity ◽  
Dendritic Growth ◽  
Magnetic Ordering ◽  
Containerless Processing ◽  
Magnetic Alloys ◽  
Dendrite Growth Velocity ◽  
Direct Measurements ◽  
Undercooled Melt ◽  
Undercooled Melts

ABSTRACTTechniques of containerless processing are applied to undercool and solidify metals and alloys. These techniques allow direct measurements of both the undercooling and the crystal growth velocity. Experimental results are presented for studies of nucleation of metastable crystalline phases and quasicrystals. Measurements of the dendrite growth velocity as a function of undercooling are exemplified for dilute Ni-based alloys and intermetallics. The results are analysed within current theories of rapid crystal growth. Their consequences on the formation of grain refined microstructures are highlighted. In addition, recent experiments on the undercooling of magnetic alloys are discussed revealing the existence of long-range magnetic ordering in an undercooled melt.

Dendrite growth velocity in the undercooled melt of glass forming Ni50Zr50 compound

2017 ◽  
Vol 97 (6) ◽  
pp. 249-256 ◽  
Author(s):  
R. Kobold ◽  
W. W. Kuang ◽  
H. Wang ◽  
W. Hornfeck ◽  
M. Kolbe ◽  
...  
Keyword(s):  
Growth Velocity ◽  
Dendrite Growth ◽  
Glass Forming ◽  
Dendrite Growth Velocity ◽  
Undercooled Melt

scholarly journals Simulation of Dendritic Growth in Solidification of Al-Cu Alloy by Applying the Modified Cellular Automaton Model with the Growth Calculation of Nucleus within a Cell

2008 ◽  
Vol 594 ◽  
pp. 22-28 ◽  
Author(s):  
Hsiun Chang Peng ◽  
Long Sun Chao
Keyword(s):  
Cellular Automaton ◽  
Directional Solidification ◽  
Growth Velocity ◽  
Dendritic Growth ◽  
Nucleation Site ◽  
Cellular Automaton Model ◽  
Cu Alloy ◽  
A Cell ◽  
Undercooled Melt ◽  
Dendritic Microstructures

Rather than designated directly as solid if the micromesh (or cell) larger than a nucleus is chosen as the nucleation site, the growth of a nucleus in the cell is considered in the application of the modified cellular automaton model to simulate the evolution of dendritic microstructures in the solidification of Al-Cu alloy. The growth velocity of a nucleus or a dendrite tip is calculated according to the KGT (Kurz-Giovanola-Trivedi) model, which is the function of the undercooling. In this study, the dendritic microstructures, such as the free dendritic growth in an undercooled melt and the dendritic growth in the directional solidification, are simulated with the modified growth algorithm in the nucleation cell. The simulated results for the temporal and final morphologies are shown and are in agreement with the experimental ones.

scholarly journals Rod eutectic growth in bulk undercooled melts

2021 ◽  
Author(s):  
Junfeng Xu ◽  
Tao Zhang ◽  
Peter Galenko
Keyword(s):  
Bessel Function ◽  
Model Calculation ◽  
Analytical Model ◽  
Growth Velocity ◽  
Growth Models ◽  
High Growth ◽  
Eutectic Growth ◽  
Lamellar Eutectic ◽  
Undercooled Melt ◽  
Undercooled Melts

This article proposes an analytical model to understand the rod-growth of eutectic in the bulk undercooled melt. Based on the previous derivations of the lamellar eutectic growth models, relaxing the assumptions of small Peclet numbers, the model is derived by considering melt kinetic and thermal undercoolings. The intent of this model is to predict the transitions in eutectic pattern for conditions of the low and high growth velocity. In addition to investigation of the transition between lamellar and rod eutectic pattern, mathematical simplifications of solving Bessel function are presented as well, which is the most important priority to model calculation.

Grain refinement induced by a critical crystal growth velocity in undercooled melts

1990 ◽  
Vol 56 (4) ◽  
pp. 324-326 ◽  
Author(s):  
R. Willnecker ◽  
D. M. Herlach ◽  
B. Feuerbacher
Keyword(s):  
Crystal Growth ◽  
Grain Refinement ◽  
Growth Velocity ◽  
Undercooled Melts

Crystal growth velocity of sodium salt hydrates

1983 ◽  
Vol 28 (1) ◽  
pp. 19-23 ◽  
Author(s):  
Dan D. Edie ◽  
Charles G. Sandell ◽  
Joseph C. Mullins
Keyword(s):  
Crystal Growth ◽  
Sodium Salt ◽  
Growth Velocity ◽  
Salt Hydrates

Defect-mediated crystal growth from deeply undercooled melts

2022 ◽  
Vol 201 ◽  
pp. 110861
Author(s):  
Zhenzhen Yan ◽  
Bin Xu ◽  
Jinfu Li ◽  
Lingti Kong
Keyword(s):  
Crystal Growth ◽  
Undercooled Melts

Phase-Field Simulation of Three-Dimensional Dendritic Growth

2010 ◽  
Vol 97-101 ◽  
pp. 3769-3772 ◽  
Author(s):  
Chang Sheng Zhu ◽  
Jun Wei Wang
Keyword(s):  
Computational Methods ◽  
Phase Field ◽  
Interfacial Energy ◽  
Dendritic Growth ◽  
Field Model ◽  
Three Dimensional ◽  
Phase Field Model ◽  
Computational Time ◽  
Field Simulation ◽  
Undercooled Melt

Based on a thin interface limit 3D phase-field model by coupled the anisotropy of interfacial energy and self-designed AADCR to improve on the computational methods for solving phase-field, 3D dendritic growth in pure undercooled melt is implemented successfully. The simulation authentically recreated the 3D dendritic morphological fromation, and receives the dendritic growth rule being consistent with crystallization mechanism. An example indicates that AADCR can decreased 70% computational time compared with not using algorithms for a 3D domain of size 300×300×300 grids, at the same time, the accelerated algorithms’ computed precision is higher and the redundancy is small, therefore, the accelerated method is really an effective method.

Critical Behavior of Crystal Growth Velocity

1991 ◽  
Vol 16 (2) ◽  
pp. 195-200 ◽  
Author(s):  
H Löwen ◽  
J Bechhoefer
Keyword(s):  
Crystal Growth ◽  
Critical Behavior ◽  
Growth Velocity
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