Correlation between glass transition temperature and Vogel-Fulcher-Tamman temperature in amorphous alloys

ABSTRACTA Ni-based amorphous alloy in Ni60Ti20Zr20 system was prepared by melting spinning. The glass transition temperature (Tg) was as high as about 760 K, the supercooled liquid region was quite wide, ΔTx = 50 K (ΔTx= Tx-Tg, Tx crystallization temperature), and the reduced glass transition temperature (Tg/Tm) was 0.60. The amorphous alloys exhibited a high tensile strength (of= 1015 MPa) at room temperature. The electrical conductivity obeyed a T12 law over the range of 15 K< T < 300 K, which can be explained by an electron-electron interaction model. After annealing the amorphous alloy into primary crystallization, a nanocomposites consisted of metastable Ti2Ni and Zr2Ni nanophases with size less than 15 nm embedded in the amorphous matrix was appeared.

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Zr–Al–Ni Amorphous Alloys with High Glass Transition Temperature and Significant Supercooled Liquid Region

Materials Transactions JIM ◽

10.2320/matertrans1989.31.177 ◽

1990 ◽

Vol 31 (3) ◽

pp. 177-183 ◽

Cited By ~ 751

Author(s):

Akihisa Inoue ◽

Tao Zhang ◽

Tsuyoshi Masumoto

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Amorphous Alloys ◽

Supercooled Liquid ◽

Supercooled Liquid Region ◽

Liquid Region ◽

High Glass Transition Temperature

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NANOSTRUCTURED AND BULK AMORPHOUS Zr-BASED ALLOYS PREPARED BY MECHANICAL ALLOYING AND ARC MELTING

International Journal of Modern Physics B ◽

10.1142/s021797920301817x ◽

2003 ◽

Vol 17 (10) ◽

pp. 2035-2044 ◽

Cited By ~ 3

Author(s):

S. BASKOUTAS ◽

P. LEMIS-PETROPOULOS ◽

V. KAPAKLIS ◽

Y. KOVEOS ◽

C. POLITIS

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Mechanical Alloying ◽

Amorphous Alloys ◽

Liquid Region ◽

X Ray ◽

Bulk Amorphous Alloys ◽

Arc Melting ◽

Amorphous Powders

We have produced powders of nanostructured and amorphous alloys as well as bulk amorphous alloys with composition Zr 64 Cu 18 Ni 10 Al 8 by mechanical alloying and by quenching arc melted melts in water cooled cooper dies, respectively. The alloys were investigated by X-ray diffraction as well as by thermal analysis in order to determine the structure and thermal properties. The mechanical alloyed amorphous powders and bulk amorphous cylinders show the same thermal and X-ray characteristics. For the amorphous powders, we find that the glass transition temperature Tg is 657 K and the crystallization temperature Tx is 752 K. For bulk amorphous alloys with the same composition prepard by arc melting and liquid quenching Tgis 655 K and the Tx is 725 K. Moreover for the bulk amorphous alloys the supercooled liquid region Δ Txg is 70 K, the reduced glass transition temperature tg is 0.557, the Lu–Liu parameter γ which represents the glass forming ability for bulk metallic glasses is 0.396 and experimentally the critical cooling rate Rc takes the value 7 K s -1.

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