Binary Ni-Ta Bulk Metallic Glasses Designed by Using a Cluster-Plus-Glue-Atom Model

2011 ◽  
Vol 688 ◽  
pp. 395-399 ◽  
Author(s):  
Jian Bing Qiang ◽  
Liang Yuan ◽  
Qing Wang ◽  
Ying Min Wang ◽  
Chuang Dong ◽  
...  

With the aid of the atomic-cluster-plus-glue-atom model (ACPGA model) proposed by Dong et al [1] for bulk metallic glasses (BMGs), the formation and characteristic of Ni-Ta binary BMGs were investigated in this work. Binary glass-forming compositions containing 56.3–62.5 at.%-Ni were obtained by a composition formula [M-Ni6Ta6]Ni3based on the ACPGA model. It was found that Ni-Ta BMGs with a diameter of 2 mm was obtained over a composition range of 59 ~ 62 at.%-Ni by copper mold casting method, which are in good agreement with our model prediction. Newly-developed Ni–Ta BMGs are a kind of extreme materials, which exhibit superior thermal stability (Tg= 993K) and a ultrahigh fracture strength of about 3.5 GPa.

2011 ◽  
Vol 399-401 ◽  
pp. 1012-1015
Author(s):  
Jian Peng Wu ◽  
Shan Dong Li ◽  
Mei Mei Liu ◽  
Xin Le Cai ◽  
Yi Hu ◽  
...  

The effect of C substitution on the glass forming ability (GFA) and soft magnetic properties of Fe-based bulk metallic glasses (BMG) Fe79.4-xCxSi3.5B5.1P8.9Mo3Mn0.1(x = 4.2, 5.2, and 7.0) alloys have been investigated. It is revealed that fully glassy alloy rods with diameters up to 4 mm can be prepared by conventional copper mold casting method even using the low-cost industrial Fe-P master alloy. Properly substituting of Fe by C gives rise to an enhancement of GFA. Moreover, all the samples exhibit good soft magnetic properties with high saturation magnetization up to 1.16 T and low coercivity of 204 A/m.


2007 ◽  
Vol 561-565 ◽  
pp. 1275-1278 ◽  
Author(s):  
Qing Wang ◽  
Chun Lei Zhu ◽  
Yan Hui Li ◽  
Jiang Wu ◽  
Chuang Dong ◽  
...  

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.


2007 ◽  
Vol 22 (1) ◽  
pp. 164-168 ◽  
Author(s):  
Hongxiang Li ◽  
Seonghoon Yi ◽  
Ho Sang Sohn

For extensive applications of bulk metallic glasses as structural materials, Fe-based bulk metallic glasses Fe73.8−xC7.0Si3.5BxP9.6Cr2.1Mo2.0Al2.0 (at.%, x = 3, 5, 7, 9) have been developed using hot metal, commercial grade pure elements, and industrial ferro-alloys. The alloy Fe68.8C7.0Si3.5B5P9.6Cr2.1Mo2.0Al2.0 can be cast into a fully amorphous rod of 5 mm in diameter through a suction casting method. The glass forming ability of the alloys can be successfully assessed by the difference of Gibbs free energy between liquid and solid phases obtained through thermodynamic calculations.


2009 ◽  
Vol 23 (06n07) ◽  
pp. 1235-1240 ◽  
Author(s):  
QING YANG ◽  
SHUJIE PANG ◽  
RAN LI ◽  
TAO ZHANG

Bulk metallic glasses (BMGs) in pseudo-ternary ( La - Ce )- Al - Cu system with high glass-forming ability (GFA) were synthesized based on the beneficial effect of the coexistence of similar elements La and Ce with similar atomic size and various valence electronic structures on GFA. With the coexistence of La and Ce in ( La x Ce 1- x )65 Al 10 Cu 25 system, bulk metallic glasses with diameters up to 12 mm can be produced by copper mold casting. Besides the high GFA, the ( La x Ce 1- x )65 Al 10 Cu 25 BMGs with x = 0.6 and 0.7 exhibit low glass transition temperature T g around 362 K and wide supercooled liquid regions ΔT x (ΔT x = T x - T g , where T x is the onset temperature of crystallization) of about 80 K. Compared with ternary La - Al - Cu and Ce - Al - Cu systems, significant improvement of GFA for the ( La - Ce )- Al - Cu system is caused by the coexistence of similar elements La and Ce , and the mechanism is discussed from a thermodynamic viewpoint.


2000 ◽  
Vol 644 ◽  
Author(s):  
Xiaofeng Gu ◽  
Li-qian Xing ◽  
T. C. Hufnagel

AbstractWe have prepared bulk metallic glasses of composition (HfxZr1-x)52.5Cu17.9Ni14.6Al10Ti5 (with x=0-1) by an arc melting/suction casting method. The density of these alloys increases by nearly 67% with increasing Hf content, which is advantageous for their potential use as kinetic energy armor-piercing projectile materials. The glass transition temperature and the melting temperature increase linearly with increasing Hf content. The reduced glass transition temperature (Tg/Tm) decreases from 0.64 (x=0) to 0.62 (x=1), indicating reduced glass-forming ability for the Hf- based alloy. The fracture strength in uniaxial compression at quasi-static strain rates also increases with increasing Hf content, reaching ∼ 2.2 GPa for Hf52.5Cu17.9Ni14.6Al10Ti5.


2007 ◽  
Vol 22 (6) ◽  
pp. 1710-1717 ◽  
Author(s):  
C.L. Qin ◽  
W. Zhang ◽  
K. Asami ◽  
H. Kimura ◽  
A. Inoue

Bulk metallic glasses (BMGs) with critical diameters of 2.5–3 mm were synthesized in the (Cu0.6Zr0.3Ti0.1)100−x−yNiyNbxsystem by copper-mold casting. These alloys exhibit a large supercooled liquid region (ΔTx) of 40–60 K and a high reduced glass transition temperature (Tg/Tl) of 0.60–0.61, indicating high glass-forming ability and high thermal stability of the supercooled liquid. The corrosion rates in 1 N HCl and 3 mass% NaCl solutions significantly decrease by simultaneous alloying with Ni and Nb elements. The addition is also effective in raising the pitting potential in chloride solutions. The addition of Ni and Nb is favorable for the alloys in forming Zr-, Ti-, and Nb-enriched highly protective surface films in HCl and NaCl solutions.


2008 ◽  
Vol 23 (7) ◽  
pp. 1940-1945 ◽  
Author(s):  
J.B. Qiang ◽  
W. Zhang ◽  
A. Inoue

The formation of bulk metallic glasses (BMGs) and their room temperature mechanical properties have been investigated in a serial of Ni65−xZr20Nb15Pdx (x = 0∼15; at.%) quaternary alloys, which are hopefully hydrogen-permeation materials. The partial substitution of Ni with Pd in Ni65Zr20Nb15 alloy has proved to be effective in improving glass-forming ability (GFA) and thermal stability. In particular, good BMG-forming compositions were revealed within the Pd content range of 2.5–12.5 at.%, and BMG rods of 3 mm in diameter were successfully made at compositions Ni57.5Zr20Nb15Pd7.5 and Ni55Zr20Nb15Pd10 by copper mold casting. The addition of Pd enhanced the thermal stability of the supercooled liquid. With an increase of Pd content, the supercooled liquid span, ΔTx = Tx − Tg, increased from 29 K at Ni65Zr20Nb15 to 47 K at Ni52.5Zr20Nb15Pd12.5. The Pd-bearing BMGs exhibited high fracture strength, which ranged from 2750 to 2850 MPa. These Pd-bearing BMGs showed a certain degree of toughness, and the highest plastic strain, about 2%, was reached in the Ni60Zr20Nb15Pd5 BMG.


Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 767
Author(s):  
Xianfeng Zhang ◽  
Xiao Cui ◽  
Zhuotong Du ◽  
Fangqiu Zu ◽  
Jinjing Li ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document