Enhancement of superelastic property in Ti–Zr–Ni–Cu alloy by using glass alloy precursor with high glass forming ability

Amorphous Ti 50 Ni (50-x) Cu x (at.%) (x = 15, 20 and 25) alloy ribbons were prepared by melt spinning, and then their crystallization behavior was investigated by optical microscopy, transmission electron microscopy, X-ray diffraction and differential scanning calorimetry. Wavenumber (Qp) decreased from 29.40 nm-1 to 29.29 nm-1 and ΔT(T g - T x ) increased from 31 K to 36 K with increasing Cu content from 15 at.% to 25 at.%, suggesting that glass forming ability of Ti – Ni – Cu alloy ribbons increased with increasing Cu content. Activation energy for crystallization decreased from 211.5 kJ/mol to 136.4 kJ/mol with increasing Cu content from 15 at.% to 25 at.%, suggesting that a stability of Ti – Ni – Cu amorphous decreased with increasing Cu content.

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FORMATION OF La-Al-Ni-Cu-Fe BULK METALLIC GLASSES WITH HIGH GLASS-FORMING ABILITY

International Journal of Modern Physics B ◽

10.1142/s021797921006485x ◽

2010 ◽

Vol 24 (15n16) ◽

pp. 2314-2319

Author(s):

YUNFEI JI ◽

SHUJIE PANG ◽

CHAOLI MA ◽

TAO ZHANG

Keyword(s):

Metallic Glasses ◽

Bulk Metallic Glasses ◽

Supercooled Liquid ◽

Supercooled Liquid Region ◽

Glass Forming Ability ◽

Main Element ◽

Heat Of Mixing ◽

Liquid Region ◽

Glass Forming ◽

Cu Alloy

The effect of alloy composition on improving glass-forming ability of La -based alloys is investigated in this work. Previous composition criteria demonstrated that the alloys with high glass-forming ability should have negative heats of mixing among the main constituent elements. In this study, the addition of Fe to a La -based La - Al - Ni - Cu alloy significantly improved the glass-forming ability, although the heat of mixing between Fe and the main element La is positive. La - Al - Ni - Cu - Fe bulk metallic glasses with diameters up to 15 mm were prepared by the method of pouring the molten alloys into a copper mold. These La - Al - Ni - Cu - Fe bulk metallic glasses exhibit relatively wide supercooled liquid region of about 50 k, and high T rg (T g /T l ) and γ(T x /(T g +T l )) values. It is found that the addition of Fe to the La - Al - Ni - Cu alloy lowers the Gibbs free energy difference between the liquid and crystalline phases in the supercooled liquid region and enhances the glass-forming ability of the alloy.

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Composition dependence of the glass-forming ability and soft magnetic properties of Fe-rich Fe–Nb–B ternary alloys

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.3139/146.111853 ◽

2019 ◽

Vol 110 (12) ◽

pp. 1116-1122

Author(s):

Man Zhu ◽

Peng Tao ◽

Lijuan Yao ◽

Zengyun Jian ◽

Fang'e Chang

Keyword(s):

Magnetic Properties ◽

Composition Dependence ◽

Glass Forming Ability ◽

Ternary Alloys ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

Glass Forming

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Induction period of the crystallization of silver nitrate solutions in ethylene glycol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19912142 ◽

1991 ◽

Vol 56 (10) ◽

pp. 2142-2147

Author(s):

Ivo Sláma

Keyword(s):

Ethylene Glycol ◽

Silver Nitrate ◽

Induction Period ◽

Glass Forming Ability ◽

Transformation Theory ◽

Concentration Region ◽

Glass Forming ◽

Temperature Transformation ◽

Silver Nitrate Solutions ◽

Nitrate Solutions

The dependence of the induction period of crystallization on supercooling was examined for the silver nitrate-ethylene glycol system over the concentration region of silver nitrate lome fraction of 0 to 0.12. Addition of AgNO3 to ethylene glycol was found to increase considerably the critical induction period of crystallization, although to a lesser extent than Ca(NO3)2, CaCl2, ZnCl2, LiCl and LiNO3 do. The effect of these salts on the critical induction period of crystallization in dimethylsulfoxide, dimethylformamide, dimethylacetamide and methanol was compared in terms of the solvent-rich composition limit of the glass-forming ability. By using the TTT(Time-Temperature-Transformation) theory, it has been deduced that the effect of the salts on the critical induction period of crystallization of ethylene glycol is probably due to the different dependences of viscosity on their concentration in ethylene glyco in the supercooling region.

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