Effect of wettability on the bulk Si growth from Si–Sn melts via zone melting directional solidification

Magnetostrictive property shows anisotropic characteristics, which are related to phase structure and crystal orientation. In this paper, phase structures and magnetostrictive properties of Fe[Formula: see text]Ga[Formula: see text] at different solidification rates during zone-melting directional solidification were studied. Results show that when the solidification rate exceeds 72 mm/h, the sample has a single A2 structure. A multiphase structure of D03 and A2 is formed when the solidification rate is 36 mm/h. The multiphase structure of L12 and A2 emerges in the sample prepared with a solidification rate of 18 mm/h. The samples with L12 and A2 multiphase structure have excellent low-field magnetostrictive properties, reaching 68 × 10[Formula: see text] under a magnetic field of 20 kA/m.

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Preparing crystalline silicon from Si-Sn solvent by zone melting directional solidification method

Materials Science in Semiconductor Processing ◽

10.1016/j.mssp.2017.06.044 ◽

2017 ◽

Vol 71 ◽

pp. 12-19 ◽

Cited By ~ 8

Author(s):

Lifeng Zhang ◽

Yusheng Ma ◽

Yaqiong Li

Keyword(s):

Directional Solidification ◽

Crystalline Silicon ◽

Zone Melting

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Effect of HfC Addition on Mechanical Properties of Nb-5Mo-2W-18Si In-Situ Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.261-263.1439 ◽

2004 ◽

Vol 261-263 ◽

pp. 1439-1444 ◽

Cited By ~ 3

Author(s):

Sheng Wu Wang ◽

Hisatoshi Hirai ◽

Tatsuo Tabaru ◽

A. Kitahara ◽

Hideto Ueno

Keyword(s):

Mechanical Properties ◽

Directional Solidification ◽

Base Composition ◽

Zone Melting ◽

Shearing Stress ◽

Floating Zone ◽

In Situ Composites ◽

Arc Melting ◽

Microcrack Propagation

Nb base in-situ composites with the base composition of Nb-5Mo-2W-18Si were prepared by conventional arc-melting and induction heating floating zone melting followed by directional solidification. To investigate the effect of HfC addition, Nb was replaced with 0, 1 and 2 mol% HfC. The in-situ composites predominantly have an eutectic microstructure consisting of Nb solid solution (NbSS) and (Nb,Mo,W))5Si3 (5-3 silicide). The strength at 1470 K and 1670 K increases without fracture toughness decreasing, with increasing the HfC content. Directional solidification also improves the strength at the high temperature. The slip band under the shearing stress occurs in the NbSS during plastic deformation, which contributes to suppress microcrack propagation. It seems that HfC addition reinforces the bonding strength at grain boundary or NbSS/5-3 silicide interface.

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The Directional Solidification, Microstructural Characterization and Deformation Behavior of β-Solidifying TiAl Alloy

Materials ◽

10.3390/ma12081203 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1203 ◽

Cited By ~ 14

Author(s):

Ning Cui ◽

Qianqian Wu ◽

Jin Wang ◽

Binjiang Lv ◽

Fantao Kong

Keyword(s):

Directional Solidification ◽

Deformation Behavior ◽

Lamellar Microstructure ◽

Microstructural Characterization ◽

Zone Melting ◽

Compression Tests ◽

Directionally Solidified ◽

Β Phase ◽

Lamellar Interface ◽

Loading Axis

A β-solidifying Ti–43Al–2Cr–2Mn–0.2Y alloy was directionally solidified by the optical floating zone melting method. The microstructure is mainly characterized by γ/α2 lamellae with specific orientations, which exhibits straight boundaries. The β phase is randomly distributed in the lamellar microstructure, indicating that the β phase cannot be directionally solidified. The directional solidification of γ/α2 lamellae was not affected by the precipitation of the β phase. Hot compression tests show that the deformation behavior of the β-containing lamellar microstructure also exhibits the anisotropic characteristic. The deformation resistance of the lamellae is lowest when the loading axis is aligned 45° to the lamellar interface. Microstructural observation shows that the decomposition of the lamellar microstructure tends to begin around the β phase, which benefits from the promotion of a soft β phase in the deformation. Moreover, the deformation mechanism of the lamellar microstructure was also studied. The bulging of the γ phase boundaries, the decomposition of α2 lamellae and the disappearance of γ/γ interfaces were considered as the main coarsening mechanisms of the lamellar microstructure.

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In Situ Investigation of Grain Migration by TGZM during Solidification in a Temperature Gradient

Materials Science Forum ◽

10.4028/www.scientific.net/msf.790-791.323 ◽

2014 ◽

Vol 790-791 ◽

pp. 323-328 ◽

Cited By ~ 2

Author(s):

Guillaume Reinhart ◽

Henri Nguyen-Thi ◽

Brice Sarpi ◽

Aboul Aziz Bogno ◽

Bernard Billia

Keyword(s):

Temperature Gradient ◽

Directional Solidification ◽

Columnar Structure ◽

European Synchrotron Radiation Facility ◽

Zone Melting ◽

Major Influence ◽

Bottom Part ◽

Directional Solidification Experiment ◽

Equiaxed Grain

Temperature Gradient Zone Melting (TGZM) occurs when a liquidsolid zone is submitted to a temperature gradient and leads to the migration of liquid droplets or channels through the solid, up the temperature gradient. TGZM has a major influence on the preparation of the initial solid-liquid interface during the stabilization phase following the directional melting of an alloy and is at the origin of the diffusion of solute towards the top part of the mushy zone. TGZM is also causing the migration up the temperature gradient of dendrite secondary arms during directional solidification, which can have a significant impact on the micro-segregation pattern of the final microstructure. In this communication we report on a directional solidification experiment carried out at the European Synchrotron Radiation Facility (ESRF) in Grenoble (France) on Al4.0 wt.% Cu alloy to study the dynamics induced by the TGZM phenomenon on an equiaxed grain that nucleated in front of a columnar structure. Based onin situexperimental observations obtained by synchrotron X-ray radiography, the dissolution of the bottom part of the equiaxed grain is characterized and measurements are compared with predictions of the TGZM theory in diffusive regime.

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Microstructure and Mechanical Properties of an Advanced Niobium Based Ultrahigh Temperature Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.3690 ◽

2007 ◽

Vol 539-543 ◽

pp. 3690-3695 ◽

Cited By ~ 22

Author(s):

X.P. Guo ◽

L.M. Gao ◽

Ping Guan ◽

K. Kusabiraki ◽

Heng Zhi Fu

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Directional Solidification ◽

Room Temperature ◽

Zone Melting ◽

Floating Zone ◽

Directionally Solidified ◽

Microstructure And Mechanical Properties ◽

Temperature Fracture ◽

Ultrahigh Temperature

The microstructure and mechanical properties including room temperature fracture toughness Kq, tensile strengthσb and elongationδ at 1250°C of the Nb based alloy directionally solidified in an electron beam floating zone melting (EBFZM) furnace have been evaluated. The microstructure is primarily composed of Nb solid solution (Nbss), α-(Nb)5Si3 and (Nb)3Si phases. After directional solidification with the moving rate of electron beam gun R being respectively 2.4, 4.8 and 7.2 mm/min, the primary Nbss dendrites, Nbss + (Nb)5Si3/(Nb)3Si eutectic colonies (lamellar or rod-like) and divorced Nb silicide plates align along the longitudinal axes of the specimens. When R = 2.4 mm/min, the best directional microstructure is obtained. Directional solidification has significantly improved theσb at 1250°C and Kq. The maximumσb occurs for the specimens with R = 2.4 mm/min and is about 85.0 MPa, meanwhile, the Kq is about 19.4 MPam1/2.

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