Solid-State Synthesis of Magnesium Base Thermoelectric Alloys via Bulk Mechanical Alloying

MRS Proceedings ◽

10.1557/proc-980-0980-ii04-02 ◽

2006 ◽

Vol 980 ◽

Author(s):

Tatsuhiko Aizawa ◽

Renbo Song

Keyword(s):

Solid State ◽

Mechanical Alloying ◽

Binary Compound ◽

Solid State Synthesis ◽

Medium Temperature ◽

Solid Solution Formation ◽

Ternary Alloy Systems ◽

Solution Formation ◽

Diffusion Controlled ◽

Electric Structure

AbstractMagnesium binary and ternary alloy systems have been popular as a thermoelectric light-weight alloy to be working in the medium temperature range. The solid-state reactivity via the bulk mechanical alloying is applied to yield these types of alloys. The diffusion-controlled solid-state synthesis is first stated as a process to yield a binary compound, Mg2X (X = Ge, Sn and Pb). This processing is further applied to directly synthesize several ternary thermoelectric alloys Mg2Si1-xGex, Mg2Si1-ySny and Mg2Sn1-zPbz for 0.0 < x, y, z < 1.0 and to evaluate their thermoelectric properties. Hot pressing is used to make full-dense billets and samples for thermoelectric measurement. The effect of germanium and tin contents on their Seebeck coefficient and band-gap is investigated to describe the p-n transition behavior and to understand the change of electric structure with solid solution formation.

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Solid State Amorphization and Alloy Parameters for High Entropy Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.990 ◽

2021 ◽

Vol 1016 ◽

pp. 990-996

Author(s):

Takeshi Nagase

Keyword(s):

Solid Solution ◽

Solid State ◽

Intermetallic Compounds ◽

Electron Irradiation ◽

Fast Electron ◽

High Entropy Alloy ◽

Solid Solution Formation ◽

High Entropy ◽

Solution Formation ◽

State Amorphization

Fast electron irradiation can induce the solid-state amorphization (SSA) of many intermetallic compounds. The occurrence of SSA stimulated by fast electron irradiation was found in the Al0.5TiZrPdCuNi high-entropy alloy (HEA). The relationship between the occurrence of SSA in intermetallic compounds under fast electron irradiation and the empirical alloy parameters for predicting the solid-solution-formation tendency in HEAs was discussed. The occurrence of SSA in intermetallic compounds was hardly predicted, only by the alloy parameters of δ or ΔHmix, which have been widely used for predicting solid-solution formation in HEAs. All intermetallic compounds with ΔHmix ≤ -35 kJ/mol and those with δ ≥ 12.5 exhibit the occurrence of SSA. This implies that the intermetallic compounds with a largely negative ΔHmix value and a largely positive δ parameter are favorable for the occurrence of SSA.

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The Solid-State Synthesis of W-25WT% Re Using a Mechanical Alloying Approach

Materials Science Forum ◽

10.4028/www.scientific.net/msf.269-272.111 ◽

1998 ◽

Vol 269-272 ◽

pp. 111-118 ◽

Cited By ~ 2

Author(s):

E.Y. Ivanov ◽

B.D. Bryskin

Keyword(s):

Solid State ◽

Mechanical Alloying ◽

Solid State Synthesis

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Structure and Magnetostriction of Tb0.7Pr0.3FeX Prepared by Solid-State Synthesis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.1459 ◽

2012 ◽

Vol 476-478 ◽

pp. 1459-1462 ◽

Cited By ~ 1

Author(s):

H.Y Yin ◽

J.J Liu ◽

R Wang ◽

X.C Liu ◽

N.K Sun ◽

...

Keyword(s):

Solid State ◽

Mechanical Alloying ◽

Annealing Process ◽

Laves Phase ◽

Type Structure ◽

Solid State Synthesis ◽

X Ray Diffraction ◽

Standard Strain ◽

X Ray ◽

Magnetoelastic Properties

Mechanical alloying (MA) was used to prepare pseudobinary high Pr-content Tb0.7Pr0.3Fex alloys. The structural and magnetoelastic properties were in investigated by means of x-ray diffraction and a standard strain technique. A single (Tb,Pr)Fe2 Laves phase with MgCu2-type structure for the composition Tb0.7Pr0.3Fe1.80 was synthesized by MA and subsequent annealing process. The high magnetostriction of 600 ppm was achieved at 10 kOe for the epoxy-bonded Tb0.7Pr0.3Fe1.8 composite.

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