Crystallization Behaviors of the Bulk Amorphous Alloy Ni60Zr25Al8Y7

2004 ◽  
Vol 449-452 ◽  
pp. 941-944
Author(s):  
W.B. Kim ◽  
B.J. Ye ◽  
S. Yi
Keyword(s):  
Amorphous Alloys ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Partial Replacement ◽  
Continuous Heating ◽  
Bulk Amorphous Alloy ◽  
Liquid Region ◽  
Optimum Amount ◽  
Crystallization Behaviors ◽  
Binary Compounds

The effects of partial replacements of Zr by Y in the alloy Ni60Zr25-xAl8Yx(x=0 and 7 at %) on the crystallization behaviors of amorphous alloys were studied using isothermally heattreated ribbons. With the partial replacement, the supercooled liquid region upon continuous heating was significantly extended indicating that crystallization can be effectively suppressed by the optimum amount of Zr replacement by Y. The first phase appeared during crystallization was identified as the ternary compound AlNi2Zr while the single exothermic event could be observed upon heating the amorphous ribbons. The AlNi2Zr phase was decomposed into binary compounds upon further heating. Therefore, the extended supercooled liquid region of the alloy Ni60Zr25Al8Y7was attributed to the suppression of AlNi2Zr phase formation by the partial replacement of Zr by Y. The effects of Y on the crystallization behaviors were discussed on the basis of atomic configuration of the supercooled liquid.

Glass-forming ability and thermal stability of Fe62Nb8−xZrxB30 and Fe72Zr8B20 amorphous alloys?

Open Physics ◽  
2004 ◽  
Vol 2 (1) ◽  
Author(s):  
M. Shapaan ◽  
J. Lábár ◽  
L. Varga ◽  
J. Lendvai
Keyword(s):  
Thermal Stability ◽  
Amorphous Alloys ◽  
Strong Dependence ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Glass Forming Ability ◽  
Partial Replacement ◽  
Liquid Region ◽  
Glass Forming ◽  
Thermal Stability Of

AbstractGlass-forming ability (GFA) and thermal stability of Fe62Nb8B30, Fe62Nb6Zr2B30 and Fe72Zr8B20 at % amorphous alloys were investigated by calorimetric (DSC and DTA) measurements. The crystallization kinetics was studied by DSC in the mode of continuous versus linear heating and it was found that both the glass transition temperature, Tg, and the crystallization peak temperature, Tp, display strong dependence on the heating rate. The partial replacement of Nb by Zr leads to lower Tg and Tx temperatures and causes a decrease of the supercooled liquid region. JMA analysis of isothermal transformation data measured between Tg and Tx suggests that the crystallization of the Fe62Nb8B30 and Fe62Nb6Zr2B30 amorphous alloys take place by three-dimensional growth with constant nucleation rate. Nb enhances the precipitation of the metastable Fe23B6 phase and stabilizes it up to the third crystallization stage. Zr addition increases the lattice constant of Fe23B6 and, at the same time, decreases the grain size.

Effects of Cr or Mo Compositions on Mechanical Behavior of Fe-Base Bulk Amorphous Alloy

2015 ◽  
Vol 1110 ◽  
pp. 136-141 ◽  
Author(s):  
Beom Taek Jang ◽  
Young In Kim
Keyword(s):  
Amorphous Alloys ◽  
Wear Test ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Bulk Amorphous Alloy ◽  
Liquid Region ◽  
Wear Property ◽  
Casting Technique ◽  
Bulk Amorphous Alloys ◽  
Mo Content

For enhancing wear property of Fe-based bulk amorphous alloys as structural materials, We investigate effects of Cr or Mo compositions on wear and mechanical behaviors of FeCSiBPMo and FeCSiBPAlCr system bulk amorphous alloys which are suction-cast into a copper mold by arc melting in an argon atmosphere using a suction casting technique. X-ray diffraction, differential scanning calorimeter and Scanning electron microscopy were used to observe the microstructure and surface morphologies. Cr-Fe or Mo-Fe substitutions led to a dramatic increase in the glass transition temperature as well as the supercooled liquid region. After the wear test, the mass loss of both BAAs decreased remarkably at higher element. Nanoindentation results indicate that with an increase of the Cr or Mo compositions, the hardness and elastic modulus increased in both BAA samples. These results suggest that wear behaviors of the BAAs corresponded to change in hardness, which means that fracture morphologies of worn surface are strongly dependent on surface hardening with high Cr or Mo content.

New Cu-Based Bulk Metallic Glasses with High Strength of 2000 MPa

2004 ◽  
Vol 449-452 ◽  
pp. 945-948 ◽  
Author(s):  
Seung Y. Shin ◽  
J.H. Kim ◽  
D.M. Lee ◽  
Jong K. Lee ◽  
H.J. Kim ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Amorphous Alloys ◽  
Ternary Phase Diagram ◽  
High Strength ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Bulk Amorphous Alloy ◽  
Liquid Region ◽  
Mold Casting ◽  
Application Fields

New Cu-based bulk amorphous alloys exhibiting a large supercooled liquid region and good mechanical properties were formed in a quaternary Cu-Ni-Zr-Ti systems consisting of only metallic elements. The compositional range for the formation of the amorphous alloys that have high glass forming ability (GFA) (> 3 mm diameter) and large supercooled liquid region (> 50 K) is defined in the pseudo-ternary phase diagram Cu-Ni-(Zr, Ti). A bulk amorphous Cu54Ni6Zr22Ti18alloy with the diameter of 6 mm can be prepared by copper mold casting. The Cu54Ni6Zr22Ti18alloy shows glass transition temperature (Tg) of 712 K, crystallization temperature (Tx) of 769 K and supercooled liquid region (ΔTx) of 57 K. The Cu54Ni6Zr22Ti18alloy exhibits high compressive fracture strength of about 2130 MPa with a plastic strain of about 1.5 %. The new Cu-based bulk amorphous alloy with high GFA and good mechanical properties allows us to expect the extension of application fields as a new engineering material.

scholarly journals Mechanically Alloyed Amorphous Ti50(Cu0.45Ni0.55)44–xAlxSi4B2 Alloys with Supercooled Liquid Region

2002 ◽  
Vol 17 (7) ◽  
pp. 1743-1749 ◽  
Author(s):  
L. C. Zhang ◽  
J. Xu ◽  
E. Ma
Keyword(s):  
Amorphous Alloys ◽  
Supercooled Liquid ◽  
High Energy ◽  
Supercooled Liquid Region ◽  
Liquid Region ◽  
Mechanically Alloyed ◽  
Scanning Calorimetry ◽  
Beneficial Effects ◽  
State Process ◽  
Transmission Electron

A high-energy ball milling procedure has been developed to produce amorphous alloys in Ti50(Cu0.45Ni0.55)44−xAlxSi4B2 (x= 0, 4, 8, 12) powder mixtures. The milling products were characterized using x-ray diffraction, differential scanning calorimetry, and transmission electron microscopy. The Ti-based amorphous alloy powders prepared through this solid-state process exhibit a well-defined glass transition and a supercooled liquid region (ΔTx =64 K) close to the largest achieved so far for Ti-based undercooled melts. The substitution of Al for Cu and Ni has beneficial effects on stabilizing the supercooled liquid. Residual nanocrystals of the αTi structure are uniformly dispersed in the amorphous matrix. The composite alloy powders offer the potential for consolidation in the supercooled liquid region to bulk lightweight amorphous alloys and the possibility to attain desirable mechanical properties.

Comments on “Fabrication of ternary Mg–Cu–Gd bulk metallic glass with high glass-forming ability under air atmosphere” [H. Men and D.H. Kim, J. Mater. Res. 18, 1502 (2003)]

2004 ◽  
Vol 19 (2) ◽  
pp. 427-428 ◽  
Author(s):  
Z.P. Lu ◽  
C.T. Liu
Keyword(s):  
Glass Transition ◽  
Metallic Glasses ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Glass Forming Ability ◽  
Bulk Amorphous Alloy ◽  
Liquid Region ◽  
Glass Forming ◽  
Air Atmosphere ◽  
Acta Mater

A new Mg-based bulk amorphous alloy (i.e., Mg65Cu25Gd10) has successfully been developed by Men and Kim [H. Men and D.H. Kim, J. Mater. Res. 18, 1502 (2003)]. They showed that this alloy exhibits significantly improved glass-forming ability (GFA) in comparison with Mg65Cu25Y10 alloy. However, this improved GFA cannot be indicated by the supercooled liquid region ΔT and the reduced glass-transition temperature Trg. As shown in the current comment, the new parameter γ, Tx/(Tg + Tl) defined in our recent papers [Z.P. Lu and C.T. Liu, Acta Mater. 50, 3501 (2002); Z.P. Lu and C.T. Liu, Phys. Rev. Lett. 91, 115505 (2003)] can well gauge GFA for bulk metallic glasses, including the current Mg-based alloys.

Ti-based amorphous alloys with a wide supercooled liquid region

2007 ◽  
Vol 61 (14-15) ◽  
pp. 2851-2854 ◽  
Author(s):  
Akihisa Inoue ◽  
Nobuyuki Nishiyama ◽  
Kenji Amiya ◽  
Tao Zhang ◽  
Tsuyoshi Masumoto
Keyword(s):  
Amorphous Alloys ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Liquid Region

Formation of Cu-Zr-Ti Amorphous Alloys with Significant Supercooled Liquid Region by Mechanical Alloying

1999 ◽  
Vol 312-314 ◽  
pp. 67-72 ◽  
Author(s):  
P.J. Desré ◽  
Chung Kwei Lin ◽  
Giin Shan Chen ◽  
Rong Fuh Louh ◽  
K.C. Chen
Keyword(s):  
Mechanical Alloying ◽  
Amorphous Alloys ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Liquid Region

scholarly journals Crystallization Behavior of Al70Fe12.5V12.5Nb5 Amorphous Alloy Formed by Mechanical Alloying

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 383 ◽  
Author(s):  
Xuan Liu ◽  
Xingfu Wang ◽  
Yongli Si ◽  
Xiaokang Zhong ◽  
Fusheng Han
Keyword(s):  
Amorphous Alloy ◽  
Mechanical Alloying ◽  
Amorphous Alloys ◽  
Crystallization Behavior ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Glass Forming Ability ◽  
Liquid Region ◽  
Application Field ◽  
Glass Forming

In this study, the formation and crystallization of the Al70Fe12.5V12.5Nb5 amorphous alloys has been investigated. The addition of Nb enhances the supercooled liquid region and glass forming ability of the Al-Fe-V amorphous alloys. The Al70Fe12.5V12.5Nb5 amorphous alloy exhibits two distinct crystallization steps and a large supercooled liquid region at more than 100 K. Kissinger and Ozawa analyses showed that the two activation energies for crystallization (Ex) were estimated to be 366.3 ± 23.9 and 380.5 ± 23.9 kJ/mol. Large supercooled liquid regions are expected to gain an application field of Al-based amorphous alloys.

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