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

2005 ◽  
Vol 20 (9) ◽  
pp. 2252-2255 ◽  
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.

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

2003 ◽  
Vol 18 (7) ◽  
pp. 1502-1504 ◽  
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.

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

2003 ◽  
Vol 18 (10) ◽  
pp. 2288-2291 ◽  
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.

Metallic glass formation in Cu–Ni–Ti (Zr, Hf) systems studied by thermodynamic calculations

RSC Advances ◽  
2016 ◽  
Vol 6 (26) ◽  
pp. 21802-21807 ◽  
Author(s):  
Y. Y. Wang ◽  
Q. Wang ◽  
J. H. Li ◽  
B. X. Liu
Keyword(s):  
Metallic Glass ◽  
Size Effect ◽  
Glass Formation ◽  
Composition Dependence ◽  
Glass Forming Ability ◽  
Thermodynamic Calculations ◽  
Mixing Enthalpy ◽  
Atomic Size ◽  
Glass Forming ◽  
The Family

The glass formation regions for the family of Cu–Ni–Ti (Zr, Hf) systems have been calculated. The composition dependence of the glass forming ability was predicted and discussed in terms of the mixing enthalpy and atomic size effect.

Understanding the Glass-forming Ability of Cu50Zr50 Alloys in Terms of a Metastable Eutectic

2005 ◽  
Vol 20 (9) ◽  
pp. 2307-2313 ◽  
Author(s):  
W.H. Wang ◽  
J.J. Lewandowski ◽  
A.L. Greer
Keyword(s):  
Metallic Glasses ◽  
Glass Formation ◽  
Composition Range ◽  
Intermetallic Phase ◽  
Glass Forming Ability ◽  
Copper Mold ◽  
Wide Composition Range ◽  
Glass Forming ◽  
Copper Mold Casting ◽  
Mold Casting

Interest in finding binary alloys that can form bulk metallic glasses has stimulated recent work on the Cu–Zr system, which is known to show glass formation over a wide composition range. This work focuses on copper mold casting of Cu50Zr50 (at.%), and it is shown that fully amorphous rods up to 2-mm diameter can be obtained. The primary intermetallic phase competing with glass formation on cooling is identified, and the glass-forming ability is interpreted in terms of a metastable eutectic involving this phase. Minor additions of aluminum increase the glass-forming ability: with addition of 4 at.% Al to Cu50Zr50, rods of at least 5-mm diameter can be cast fully amorphous. The improvement of glass-forming ability is related to suppression of the primary intermetallic phase.

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

2005 ◽  
Vol 20 (9) ◽  
pp. 2379-2385 ◽  
Author(s):  
E.S. Park ◽  
J.Y. Lee ◽  
D.H. Kim
Keyword(s):  
Metallic Glass ◽  
Bulk Metallic Glass ◽  
Compressive Loading ◽  
Glass Forming Ability ◽  
Partial Substitution ◽  
Casting Method ◽  
Glass Forming ◽  
Air Atmosphere ◽  
Mold Casting ◽  
Ag Substitution

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.

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

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 %.

Enhancing bulk metallic glass formation in Ni–Nb–Sn-based alloys via substitutional alloying with Co and Hf

2008 ◽  
Vol 23 (3) ◽  
pp. 688-699 ◽  
Author(s):  
Li Zhang ◽  
Mu-Jin Zhuo ◽  
Jian Xu
Keyword(s):  
Metallic Glass ◽  
Ternary System ◽  
Metallic Glasses ◽  
Glass Formation ◽  
Composition Range ◽  
Glass Forming Ability ◽  
Partial Substitution ◽  
Wide Composition Range ◽  
Positive Effects ◽  
Glass Forming

Bulk metallic glasses have been formed over a fairly wide composition range (54–62 at.% Ni, 32–36 at.% Nb, and 3–11 at.% Sn) in the Ni–Nb–Sn ternary system. Partial substitution of Co for Ni and Hf for Nb improves the glass-forming ability, eventually leading to 4 mm glassy rods at the Ni56Co3Nb28Hf8Sn5 composition. The positive effects of these alloying elements have been explained based on a systematic monitoring of the amount and morphology of the competing crystalline phases as a function of the Co and Hf contents.

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

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.

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

2013 ◽  
Vol 747-748 ◽  
pp. 217-222 ◽  
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.

Studies on Fe-Cr-Ni-Si-B Bulk Metallic Glass for Automotive Applications

2015 ◽  
Vol 1114 ◽  
pp. 68-75
Author(s):  
Mariana Lucaci ◽  
Delia Patroi ◽  
Violeta Tsakiris ◽  
Magdalena Valentina Lungu ◽  
Eugen Manta ◽  
...  
Keyword(s):  
Metallic Glass ◽  
Bulk Metallic Glass ◽  
Metallic Glasses ◽  
Melt Spinning ◽  
Copper Mold ◽  
Technological Parameters ◽  
Glass Forming ◽  
Copper Mold Casting ◽  
Mold Casting ◽  
Melt Spin

Researches and developments were carried out for obtaining of bulk metallic glass (BMG) from the Fe-Cr-Ni-Si-B system. The used processing methods were copper mold casting and melt spinning method. The resulted materials are in form of sheets with sizes of 69.7 x 64 x 3/1.5 mm and of strips with thickness less than 50 microns, which were obtained by varying the melt spin technological parameters. The both processing variants are not suitable for obtaining such of alloy in bulk metallic glass form. Adding of zirconium to this alloy produces bulk metallic glasses only for the melt spin products. The DSC analysis emphases that the zirconium modified alloy processed by melt spinning method exhibits a high glass forming ability (GFA).

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