Formation and properties of Pr-based bulk metallic glasses

2006 ◽  
Vol 21 (2) ◽  
pp. 369-374 ◽  
Author(s):  
Z.F. Zhao ◽  
P. Wen ◽  
R.J. Wang ◽  
D.Q. Zhao ◽  
M.X. Pan ◽  
...  
Keyword(s):  
Glass Transition ◽  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
Glass Forming Ability ◽  
Point Of View ◽  
Compositional Dependence ◽  
Phonon Softening ◽  
Glass Forming ◽  
Large Bulk ◽  
Structural Point

The data on the compositional dependence of glass-forming ability, glass transition, and properties of bulk metallic glasses (BMGs) are important for understanding the nature and glass-forming ability of metallic glasses and for their application. In this paper, we report the formation of rare-earth-based Pr–(Cu,Ni)–Al pseudo-ternary BMGs with a large bulk glass-forming composition range and distinct glass transition. The compositional dependence of glass-forming ability, glass transition, and properties were systematically studied. The contrasting effects of Al and Pr on glass formation and glass transition, unique elastic properties, and phonon softening of the BMGs are discussed from the structural point of view.

Glass Forming Ability of Ca-Based Bulk Metallic Glasses

2011 ◽  
Vol 171 ◽  
pp. 121-126 ◽  
Author(s):  
Ashmi T. Patel ◽  
Kirit N. Lad ◽  
Arun Pratap
Keyword(s):  
Metallic Glasses ◽  
Driving Force ◽  
Bulk Metallic Glasses ◽  
Energy Difference ◽  
Glass Forming Ability ◽  
Point Of View ◽  
Undercooled Liquid ◽  
Free Energy Difference ◽  
Glass Forming ◽  
Gibbs Free Energy Difference

Knowledge of glass forming ability (GFA) of amorphous metallic alloys is very important from both theoretical and practical point of view. Thermodynamically, the Gibbs free energy difference, ΔG between the undercooled liquid and the corresponding crystalline state is driving force for crystallization. As a consequence, it is a good indicator for glass forming ability of metallic glasses. A novel expression for ΔG has been used to estimate the GFA of recently developed Ca-based bulk metallic glasses viz. Ca53Mg23Cu24,Ca65Mg15Cu20,Ca40Mg25Cu35, Ca50Mg22.5Cu27.5 and Ca55Mg15Cu30. Different GFA criteria are also evaluated for systems taken up in the study and effect of addition of variation in composition of Ca-Mg-Cu system is also investigated. Present work suggests that among different GFA criteria, ΔG is the best criterion for the prediction of GFA for Ca-based bulk metallic glasses.

GLASS FORMING ABILITY AND KINETIC CHARACTERS OF PARAMAGNETIC Nd60Co40-xAlx(x=5, 10, 15) BULK METALLIC GLASSES

2004 ◽  
Vol 18 (14) ◽  
pp. 679-685 ◽  
Author(s):  
L. XIA ◽  
Y. D. DONG
Keyword(s):  
Glass Transition ◽  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Glass Forming Ability ◽  
Ternary Alloys ◽  
Liquid Region ◽  
Scanning Calorimetry ◽  
Glass Forming

Paramagnetic Nd 60 Co 40-x Al x(x=5, 10, 15) bulk metallic glasses (BMGs) were prepared in the shape of rods 2 mm in diameter by suction casting. The ternary alloys have shown distinct glass transitions in Differential Scanning Calorimetry (DSC) measurements and excellent glass-forming ability. The glass transition and crystallization behaviors as well as their kinetics have been studied. The reduced glass transition temperature and the supercooled liquid region of the alloys were found to increase with the increasing content of Al . The role of Al was discussed. The parameter γ defined by Liu et al. was employed to discuss the glass-forming ability of the alloys and the critical cooling rates as well as the critical section thickness of the alloys were predicted accordingly.

Cu−Zr−Ti ternary bulk metallic glasses correlated with (L → Cu8Zr3 + Cu10Zr7) univariant eutectic reaction

2008 ◽  
Vol 23 (5) ◽  
pp. 1249-1257 ◽  
Author(s):  
Chun-Li Dai ◽  
Jing-Wei Deng ◽  
Ze-Xiu Zhang ◽  
Jian Xu
Keyword(s):  
Glass Transition ◽  
Metallic Glasses ◽  
Eutectic Reaction ◽  
Glass Forming Ability ◽  
Compositional Dependence ◽  
Copper Mold ◽  
Glass Forming ◽  
Copper Mold Casting ◽  
Mold Casting ◽  
Ti Content

Starting from Cu60Zr30Ti10, the compositional dependence of bulk metallic glass (BMG) formation was revisited in the Cu−Zr−Ti ternary system. It was revealed that the optimal BMG-forming composition is located at Cu60Zr33Ti7, for which a monolithic BMG rod 4 mm in diameter can be fabricated using copper mold casting. This composition is along, although slightly off, the univariant eutectic groove for the reaction (L → Cu8Zr3 + Cu10Zr7). With respect to the corresponding Cu−Zr binary alloys, Ti has a significant effect on further stabilizing the liquid, thus increasing the glass-forming ability. For the Cu60Zr40−yTiy (3 ⩽ y ⩽ 10) series BMGs, the glass transition temperature Tg decreased with increasing Ti content, at a rate of about 2.8 K/at.%. Among these BMGs, significant compositional dependence of compressive plasticity is not observed, irrespective of the Tg change. Cu60Zr33Ti7 glass exhibits maximum fracture strength around 2160 MPa.

On The Glass Forming Ability Criteria Of Bulk Metallic Glasses

2002 ◽  
Vol 754 ◽  
Author(s):  
Z. P. Lu ◽  
C. T. Liu
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Metallic Glasses ◽  
Glass Formation ◽  
Liquidus Temperature ◽  
Bulk Metallic Glasses ◽  
Glass Forming Ability ◽  
Glass Forming ◽  
Onset Crystallization Temperature ◽  
New Criterion

ABSTRACTA new criterion γ, defined as Tx/(Tg+Tl) (where Tx is the onset crystallization temperature, Tg the glass transition temperature and Tl the liquidus temperature), has been proposed for glass formation in bulk metallic glasses (BMGs). The interrelationship between this new parameter and glass-forming ability (GFA) was elaborated and discussed in comparison with other established criteria. It was found that the new criterion γ had a much better correlation with GFA than other established parameters. An approximation of the critical cooling rate for glass formation was also formulated and evaluated in the light of this new parameter.

Bulk Metallic Glasses: Aluminum-Based

2019 ◽  
Author(s):  
B.J. Yang ◽  
J.H. Yao ◽  
J.Q. Wang ◽  
Y.S. Chao ◽  
E. Ma
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Thermal Properties ◽  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
Systematic Investigation ◽  
Glass Forming Ability ◽  
Atomic Cluster ◽  
Glass Forming ◽  
Thermal Stability Of

This paper details a systematic investigation of the formation of Al-based bulk metallic glasses, expanding on an earlier brief report.[] We discuss an approach for designing and predicting the best glass-forming composition in the Al–TM–RE systems, based on the atomic cluster packing model for the internal structure of the glass. The effects of additional elements in quaternary and quinary systems on the glass-forming ability and thermal stability of the glasses are also discussed. Three new compositions, Al86Ni6Y4.5Co2La1.5, Al86Ni7Y5Co1La1 and Al86Ni7Y4.5Co1La1.5, are capable of forming fully glassy rods of 1 mm in diameter; their glass transition and other thermal properties are systematically characterized.

scholarly journals On Glass Forming Ability of Bulk Metallic Glasses by Relating the Internal Friction Peak Value

Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 767
Author(s):  
Xianfeng Zhang ◽  
Xiao Cui ◽  
Zhuotong Du ◽  
Fangqiu Zu ◽  
Jinjing Li ◽  
...  
Keyword(s):  
Internal Friction ◽  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
Glass Forming Ability ◽  
Liquid Region ◽  
Internal Friction Peak ◽  
Glass Forming ◽  
Constituent Elements ◽  
Valid Criterion ◽  
Peak Value

The internal friction (IF) behaviors of a series of LaCe-, Zr-, and La-based bulk metallic glasses (BMGs) were studied by a computer-controlled, conventional inverted torsion pendulum. The results indicate that with an increasing temperature, the IF also increases gradually in the supercooled liquid region, followed by a decrease caused by crystallization. BMGs with a good glass forming ability (GFA) usually possess a high IF peak value for an alloy system with the same constituent elements. Furthermore, the magnitude of the IF value (Qi−1) of the inflection point is an efficient criterion of GFA. The Qi−1 value is a valid criterion under the conditions of identical constituent elements and different element contents. However, Qi−1 and GFA have no relationship among different alloy systems.

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