Effect of Ag Addition on the Improvement of Glass-forming Ability and Plasticity of Mg–Cu–Gd Bulk Metallic Glass

The effect of Ag substitution for Cu on the glass forming ability (GFA) and mechanical properties of Mg65Cu25−xAgxGd10 (x = 0, 5, 10, 15, 20, 25) alloyswere investigated using x-ray diffractometry and differential scanning calorimetry.The partial substitution of Cu by Ag in Mg65Cu25Gd10 promoted the GFA. Mg65Cu20Ag5Gd10 bulk metallic glass (BMG) with a diameter of 11 mm could be fabricated by conventional copper-mold casting method in air atmosphere. The Mg65Cu20Ag5Gd10 BMG exhibits yielding and plastic deformation during compressive loading. The compressive fracture strength, total strain to failure, and plastic strain to failure of the Mg65Cu20Ag5Gd10 BMG were 909 MPa, 2.21% and 0.5%, respectively.

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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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Improvement of glass forming ability and magnetic properties of a Gd55Al20Co25 bulk metallic glass by minor Fe substitution for Co

Modern Physics Letters B ◽

10.1142/s0217984915501985 ◽

2015 ◽

Vol 29 (31) ◽

pp. 1550198 ◽

Cited By ~ 1

Author(s):

Q. Guan ◽

P. Yu ◽

K. C. Chan ◽

L. Xia

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Glass Forming Ability ◽

Magnetic Entropy ◽

Casting Method ◽

Glass Forming ◽

Caloric Effect ◽

Fe Substitution

[Formula: see text] bulk metallic glass (BMG) exhibits good glass forming ability (GFA) and excellent magneto-caloric effect (MCE). In order to further improve the GFA and MCE of the [Formula: see text] BMG, we attempted to add small amount of Fe as a replacement of Co in the BMG and obtained [Formula: see text] glassy rod using a traditional suction casting method. The [Formula: see text] BMG shows a better GFA and MCE than the [Formula: see text] BMG. The magneto-caloric behavior of the [Formula: see text] BMG was investigated by studying the field dependence of the magnetic entropy change peak and the refrigeration capacity.

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A new Mg65Cu7.5Ni7.5Zn5Ag5Y10 bulk metallic glass with strong glass-forming ability

Journal of Materials Research ◽

10.1557/jmr.2003.0319 ◽

2003 ◽

Vol 18 (10) ◽

pp. 2288-2291 ◽

Cited By ~ 66

Author(s):

H. Ma ◽

E. Ma ◽

J. Xu

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Glass Forming Ability ◽

Copper Mold ◽

Glass Forming ◽

Copper Mold Casting ◽

Mold Casting

We report a new Mg-based bulk metallic glass-forming alloy: Mg65Cu7.5Ni7.5Zn5 Ag5Y10. The alloy exhibits a glass-forming ability significantly stronger than all previously discovered Mg-based glass formers. Fully glassy rods 9 mm in diameter can be obtained by using copper mold casting. The critical cooling rate for glass formation was estimated to be <50 Ks−1. The reduced glass-transition temperature (Trg) of the glass was determined to be 0.59.

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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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Formation of a New Mg-Cu-Ni-Gd Bulk Metallic Glass: Effects of Rare Earth on Glass-Forming Ability of Mg-Tm-Re Bulk Metallic Glasses

Materials Science Forum ◽

10.4028/www.scientific.net/msf.747-748.217 ◽

2013 ◽

Vol 747-748 ◽

pp. 217-222 ◽

Cited By ~ 1

Author(s):

Jian Yin ◽

Zhi Jian Zhou ◽

Zhi Peng Qi ◽

Yi Liu

Keyword(s):

Rare Earth ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Formation Enthalpy ◽

Glass Forming Ability ◽

Glass Forming ◽

Mold Casting ◽

Strength And Plasticity ◽

High Level ◽

Re Elements

A new Mg65Cu18Ni6Gd11 bulk metallic glass (BMG) with high level of Ni content, exhibiting glass-forming ability (GFA) of 6 mm, was fabricated by copper mold casting. The compressive strength and plasticity of the Mg65Cu18Ni6Gd11 BMG were 938 MPa and 0.14%, respectively. The composition design of the Mg65Cu18Ni6Gd11 BMG with enhanced GFA had succeeded simply using Gd substituting Y in the Mg65Cu18Ni6Y11 BMG, which was a result of a comparison on the GFA between the Mg-TM-Gd and Mg-TM-Y BMGs (TM: transition metals). Compared to the Mg-TM-Y BMGs, the Mg-TM-Gd BMGs exhibited improved GFA, which was demonstrated to be mainly attributed to the more negative amorphous formation enthalpy resulting from Gd substituting Y. The effects of rare earth (RE) elements on the GFA of Mg-TM-RE were discussed. This work may suggest an easy way for developing new Mg-based BMGs with improved GFA by rare earth (RE) design.

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Formation of Mg–Cu–Ni–Ag–Zn–Y–Gd Bulk Glassy Alloy by Casting into Cone-shaped Copper Mold in Air Atmosphere

Journal of Materials Research ◽

10.1557/jmr.2005.0181 ◽

2005 ◽

Vol 20 (6) ◽

pp. 1465-1469 ◽

Cited By ~ 39

Author(s):

E.S. Park ◽

D.H. Kim

Keyword(s):

Glass Formation ◽

Glassy Alloy ◽

Compressive Loading ◽

Maximum Diameter ◽

Copper Mold ◽

Casting Method ◽

Glass Forming ◽

Air Atmosphere ◽

Mold Casting ◽

Bulk Glassy Alloy

A new Mg–Cu–Ni–Ag–Zn–Y–Gd alloy with significantly improved glass forming ability (GFA) was developed in this work. Mg65Cu7.5Ni7.5Ag5Zn5Y5Gd5 bulk metallic glass (BMG) with a diameter of 14 mm was successfully fabricated by conventional copper mold casting method in air atmosphere. The critical cooling rate for glass formation was estimated to be about 20 K/s. When the maximum diameter for glass formation was compared with those previously reported for Mg-based alloys, the Mg65Cu7.5Ni7.5Ag5Zn5Y5Gd5 alloy showed the highest GFA. However, when the GFA was compared with those of Mg-TM-RE alloys (TM: Cu, Ni, Zn, and Ag; RE: Y and Gd), the significant improved GFA of the Mg–Cu–Ni–Zn–Ag–Y–Gd alloy cannot be properly represented by ΔTx, Trg, K, and γ parameters. In contrast to most of the Mg-based BMGs reported so far, the Mg65Cu7.5Ni7.5Ag5Zn5Y5Gd5 BMG exhibits yielding and plastic deformation during compressive loading.

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