Correlation of the glass formation and phase selection of the Mg-Cu-Gd bulk metallic glass forming alloys

The present paper investigates the bulk metallic glass formation in Co-based alloy systems with the guidance of the cluster line and minor-alloying principles. The selected basic ternary Co-B-Si alloy compositions are intersecting points of cluster lines, defined by linking special binary clusters to the third element. Then these basic ternary alloys are further minor-alloyed with Nb and quaternary bulk metallic glasses are obtained only by 4-5 at. % Nb minor-alloying of the basic composition Co68.6B25.7Si5.7 that is developed from dense-packed cluster Co8B3. The bulk metallic glasses are expressed approximately with a unified simple composition formula: (Co8B3)1(Si,Nb)1. In addition, a quantity of Fe substitution for Co further improves the glass-forming abilities.

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Fabrication of ternary Mg–Cu–Gd bulk metallic glass with high glass-forming ability under air atmosphere

Journal of Materials Research ◽

10.1557/jmr.2003.0207 ◽

2003 ◽

Vol 18 (7) ◽

pp. 1502-1504 ◽

Cited By ~ 130

Author(s):

H. Men ◽

D. H. Kim

Keyword(s):

Metallic Glass ◽

Cooling Rate ◽

Bulk Metallic Glass ◽

Glass Formation ◽

Glass Forming Ability ◽

Casting Method ◽

Glass Forming ◽

Air Atmosphere ◽

Mold Casting ◽

Order Of Magnitude

A new Mg65Cu25Gd10 alloy having significantly improved glass-forming ability (GFA) has been developed. In this article, we show that the ternary Mg65Cu25Gd10 bulk metallic glass with diameter of at least 8 mm can successfully be fabricated by a conventional Cu-mold casting method in air atmosphere. The critical cooling rate for glass formation was estimated on the order of magnitude of approximately 1 K/s. When compared with the GFA of Mg65Cu25Y10 alloy, the significantly improved GFA of Mg65Cu25Gd10 alloy cannot be explained by ΔTx and Trg values.

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Room-Temperature Mechanical Properties and Glass Formation of Zr50Cu20Ni15Al(15-X)Tix (x=3, 5, 7) Bulk Metallic Glass Alloys

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.66-68.741 ◽

2011 ◽

Vol 66-68 ◽

pp. 741-746

Author(s):

Jia Hua Zou ◽

Zhi Chen Zhang ◽

Shu Quan Sun

Keyword(s):

Mechanical Properties ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Metallic Glasses ◽

Glass Formation ◽

Room Temperature ◽

Glass Forming Ability ◽

Glass Forming ◽

Ti Content ◽

Ti Addition

In the present study, the Zr-Cu-Ni-Al based bulk metallic glasses with different Ti addition was successfully prepared by suction casting . It was found that the glass forming ability was improved with increasing of Ti content from 3 at.% to 7 at.%. However, with increasing of Ti content, the room-temperature plasticity decreased from 4.33% to 0.66 %.

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Doubling the Critical Size for Bulk Metallic Glass Formation in the Mg–Cu–Y Ternary System

Journal of Materials Research ◽

10.1557/jmr.2005.0307 ◽

2005 ◽

Vol 20 (9) ◽

pp. 2252-2255 ◽

Cited By ~ 76

Author(s):

H. Ma ◽

Q. Zheng ◽

J. Xu ◽

Y. Li ◽

E. Ma

Keyword(s):

Metallic Glass ◽

Ternary System ◽

Bulk Metallic Glass ◽

Glass Formation ◽

Composition Dependence ◽

Critical Size ◽

Glass Forming Ability ◽

Glass Forming ◽

Copper Mold Casting ◽

Mold Casting

Mg−Cu−Y alloys with optimal glass forming ability have been found at off-eutectic compositions. The critical size for bulk metallic glass formation at the pinpointed compositions more than doubles that of the previously discovered eutectic Mg65Cu25Y10 alloy, leading to fully glassy rods with near-centimeter diameters in the ternary system upon copper mold casting. The result is a striking demonstration of the strong composition dependence of the glass forming ability, as well as of the need to scrutinize off-eutectic compositions. The implications of the discovery are discussed.

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Effect of Compositional Short Range Order on Glass Formation in Binary Metallic System

MRS Proceedings ◽

10.1557/proc-754-cc6.16 ◽

2002 ◽

Vol 754 ◽

Author(s):

Hao Chen ◽

Mahadevan Khantha ◽

Takeshi Egami

Keyword(s):

Glass Transition ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Glass Formation ◽

Short Range ◽

Short Range Order ◽

Glass Forming Ability ◽

Range Order ◽

Dynamics Simulation ◽

Glass Forming

ABSTRACTMolecular Dynamics simulation was carried out to study the glass transition and crystallization in the metal-metalloid binary system with pair-wise potentials. The results show that a repulsive potential between metalloid (small) atoms increases the glass forming ability. The observation is consistent with the recent theory of bulk metallic glass formation through local glass transition and nano-glass formation. The theory predicted that the compositional short-range order (CSRO) prevents the small atom pairing so as to increase the glass forming ability (GFA). The present results demonstrate the important role of CSRO in bulk metallic glass formation.

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