In situ observation of interaction between grain boundaries during directional solidification of Si

Silicon facet formation during directional solidification is simulated by cellular automaton (CA) modeling in which anisotropic interfacial energy and kinetics are considered. Numerical simulations were performed with different anisotropy strengths of interfacial energy and they show good agreement with analytical equilibrium shapes obtained by the Gibbs-Thomson equation. We also compare our results of anisotropic kinetics with in situ observation experiments and the results of the phase model to verify the accuracy of our model. Simulation results of facet formation show that perturbation is promoted to the corner by the negative temperature gradient of the interface and the heat accumulation location leads to the disappearance of small corners.

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ARTEX — In situ observation of directional solidification of binary aluminium alloys on TEXUS

Microgravity Science and Technology ◽

10.1007/bf02945959 ◽

2005 ◽

Vol 16 (1-4) ◽

pp. 111-115 ◽

Cited By ~ 5

Author(s):

S. Steinbach ◽

L. Ratke

Keyword(s):

Directional Solidification ◽

Aluminium Alloys ◽

In Situ Observation

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In-Situ Observation of Microcracking in a Tial-Cr-V Alloy Under Compressive Stress

MRS Proceedings ◽

10.1557/proc-364-1041 ◽

1994 ◽

Vol 364 ◽

Author(s):

Z. J. Pu ◽

Y. Q. Liu ◽

K. H. Wu

Keyword(s):

Grain Boundaries ◽

Compressive Stress ◽

Lamellar Microstructure ◽

Compressive Deformation ◽

In Situ Observation ◽

Duplex Structure ◽

Entire Process ◽

Fully Lamellar ◽

Electronic Microscope

AbstractThe entire process of microcrack nucleation in a TiAl-Cr-V alloy with different microstructures is observed in situ by a scanning electronic microscope (SEM) during compressive deformation. The main results are summarized as follows: (1) In the fully lamellar microstructure, the microcracks nucleate mainly at the lamellar grain boundaries between soft-orientation and hard-orientation grains. (2) In the Widmanstatten structure, the microcracks distribute mainly at the intersection between two Widmanstatten plates. (3) In the duplex structure, the microcracks form at the lamella/ lamella and lamella/gamma boundaries. (4) In the nearly gamma structure, microcracks nucleate at gamma/gamma grain boundaries.

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In Situ Observation of Melting and Solidification

MRS Proceedings ◽

10.1557/proc-589-117 ◽

1999 ◽

Vol 589 ◽

Author(s):

H. Saka ◽

S. Arai ◽

S. Muto ◽

H. Miyai ◽

S. Tsukimoto

Keyword(s):

Electron Microscope ◽

Grain Boundaries ◽

Eutectic Alloy ◽

Atomic Structure ◽

In Situ Observation ◽

Metallic Materials ◽

Experimental Image ◽

In Situ Heating ◽

Melting And Solidification

AbstractMelting and solidification of metallic materials have been observed directly using an in-situ heating experiment in an electron microscope. In pure Al melting initiates at the surface, while in a eutectic alloy melting initiates preferentially at eutectic interfaces and grain boundaries. The atomic structure of a solidliquid interface was identified by comparing an experimental image with computed ones.

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