Thermal stability, corrosion resistance, and surface analysis of Cu–Hf–Ti–Ni–Nb bulk metallic glasses

2009 ◽  
Vol 24 (2) ◽  
pp. 316-323 ◽  
Author(s):  
C.L. Qin ◽  
W. Zhang ◽  
K. Asami ◽  
N. Ohtsu ◽  
A. Inoue
Keyword(s):  
Thermal Stability ◽  
Corrosion Resistance ◽  
Metallic Glasses ◽  
Surface Film ◽  
Bulk Metallic Glasses ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Liquid Region ◽  
Copper Mold Casting ◽  
Mold Casting

Bulk metallic glasses (BMGs) with high thermal stability and good corrosion resistance were synthesized in the (Cu0.6Hf0.25Ti0.15)100−x−yNiyNbx system by copper mold casting. The addition of Ni element causes an extension of a supercooled liquid region (ΔTx = Tx – Tg) from 60 K for Cu60Hf25Ti15 to 70 K for (Cu0.6Hf0.25Ti0.15)95Ni5. The simultaneous addition of Ni and Nb to the alloy is effective in improving synergistically the corrosion resistance in 1 N HCl, 3 mass% NaCl, and 1 N H2SO4 + 0.01 N NaCl solutions. The highly protective Hf-, Ti-, and Nb-enriched surface film is formed by the rapid initial preferential dissolution of Cu and Ni, which is responsible for the high corrosion resistance of the alloys in the solutions examined.

Influence of alloying elements Ni and Nb on thermal stability and corrosion resistance of Cu-based bulk metallic glasses

2007 ◽  
Vol 22 (6) ◽  
pp. 1710-1717 ◽  
Author(s):  
C.L. Qin ◽  
W. Zhang ◽  
K. Asami ◽  
H. Kimura ◽  
A. Inoue
Keyword(s):  
Thermal Stability ◽  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Liquid Region ◽  
Surface Films ◽  
Pitting Potential ◽  
Glass Forming ◽  
Mold Casting

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.

scholarly journals Investigation of the Structural Heterogeneity and Corrosion Performance of the Annealed Fe-Based Metallic Glasses

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 929
Author(s):  
Dandan Liang ◽  
Jo-Chi Tseng ◽  
Xiaodi Liu ◽  
Yuanfei Cai ◽  
Gang Xu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Passive Film ◽  
Metallic Glasses ◽  
Function Analysis ◽  
Supercooled Liquid ◽  
Structural Heterogeneity ◽  
Coordination Shell ◽  
Supercooled Liquid Region ◽  
Liquid Region ◽  
Corrosion Performance

This study investigated the structural heterogeneity, mechanical property, electrochemical behavior, and passive film characteristics of Fe–Cr–Mo–W–C–B–Y metallic glasses (MGs), which were modified through annealing at different temperatures. Results showed that annealing MGs below the glass transition temperature enhanced corrosion resistance in HCl solution owing to a highly protective passive film formed, originating from the decreased free volume and the shrinkage of the first coordination shell, which was found by pair distribution function analysis. In contrast, the enlarged first coordination shell and nanoscale crystal-like clusters were identified for MGs annealed in the supercooled liquid region, which led to a destabilized passive film and thereby deteriorated corrosion resistance. This finding reveals the crucial role of structural heterogeneity in tuning the corrosion performance of MGs.

Fe-based bulk metallic glasses with a larger supercooled liquid region and high ductility

2008 ◽  
Vol 498 (1-2) ◽  
pp. 464-467 ◽  
Author(s):  
K.Q. Qiu ◽  
J. Pang ◽  
Y.L. Ren ◽  
H.B. Zhang ◽  
C.L. Ma ◽  
...  
Keyword(s):  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Liquid Region ◽  
High Ductility

Magnetic Properties and Glass Forming Ability of Fe-B-Y-Nb-Zr Bulk Metallic Glasses

2012 ◽  
Vol 577 ◽  
pp. 27-30 ◽  
Author(s):  
San Xin Wang ◽  
Ze Yu Wu
Keyword(s):  
Thermal Stability ◽  
Magnetic Properties ◽  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
Supercooled Liquid Region ◽  
Glass Forming Ability ◽  
Maximum Diameter ◽  
Liquid Region ◽  
Casting Technique ◽  
Glass Forming

Bulk metallic glasses (BMGs) alloys (Fe71.2B24Y4.8)96Nb4-xZrx (x = 1-4 at.%) with a maximum diameter of 5 mm were synthesized with low purity materials by copper mold casting technique. The effect of Zr substitution for Nb on the structure, thermal stability and the magnetic properties has been studied. It was found that the substitution of an appropriate amount of Zr for Nb can improve the glass forming ability. The wide supercooled liquid region ∆Tx (exceeding 123 K) and a high Tg (exceeding 868 K) demonstrated a high thermal stability of the present Fe-based BMGs. In addition, these BMGs also exhibit good soft magnetic properties with relatively high saturation magnetization of 88 emu/g, and low coercivity of 20 Oe.

Formation of Bulk Glassy Fe75–x–yCrxMoyC15B10 Alloys and Their Corrosion Behavior

2002 ◽  
Vol 17 (3) ◽  
pp. 701-704 ◽  
Author(s):  
Shujie Pang ◽  
Tao Zhang ◽  
Katsuhiko Asami ◽  
Akihisa Inoue
Keyword(s):  
Corrosion Resistance ◽  
Alloy System ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Large Temperature ◽  
Liquid Region ◽  
High Corrosion Resistance ◽  
High Corrosion ◽  
Glassy Alloys ◽  
Mold Casting

Formation of bulk Fe-based glassy alloys with high corrosion resistance was succeeded in the Fe75–x–yCrxMoyC15B10 alloy system. A large temperature interval of supercooled liquid region (ΔTx) of 40–90 K was obtained over a wide composition range for the Fe75?x–yCrxMoyC15B10 alloys. The Fe75–x–yCrxMoyC15B10 alloys were prepared in a bulk glassy form with diameters of 1.0–2.5 mm by copper mold casting. The bulk glassy Fe75–x–yCrxMoyC15B10 alloys exhibited high corrosion resistance in 1 N HCl solution. The glassy alloys containing Cr were spontaneously passivated with a wide passive region before the transpassive dissolution of Cr. The passive current density decreased significantly with an increase of alloying Cr content, indicating that the addition of Cr was effective on enhancing the corrosion resistance. Excess addition of Mo for replacing Fe in the present alloys was detrimental for the corrosion resistance.

Formation, corrosion behavior, and mechanical properties of bulk glassy Zr–Al–Co–Nb alloys

2003 ◽  
Vol 18 (7) ◽  
pp. 1652-1658 ◽  
Author(s):  
Shujie Pang ◽  
Tao Zhang ◽  
Katsuhiko Asami ◽  
Akihisa Inoue
Keyword(s):  
Open Circuit Potential ◽  
Fracture Strain ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Open Circuit ◽  
Liquid Region ◽  
Copper Mold Casting ◽  
Pitting Corrosion Resistance ◽  
Mold Casting ◽  
Nb Content

Bulk glassy Zr55Al20–xCo25Nbx (x = 0 to 5 at.%) alloys with critical diameters of 2.5–5 mm and supercooled liquid region of 48–75 K were produced by copper-mold casting. These alloys were spontaneously passivated in 3 mass% NaCl and 1 N H2SO4 solutions. The addition of Nb to the alloy enhanced the pitting corrosion resistance in the NaCl solution and enabled the open-circuit potential in the H2SO4 solution. Zr- and Al-enriched passive films formed on the bulk glassy Zr–Al–Co–Nb alloys exposed to air and on those immersed in the solutions. The increase in Nb content of the alloys resulted in an increase in Zr and Nb concentrations and a decrease in Al concentration of the passive film. The Vickers hardness, Young's modulus, compressive fracture strength, fracture strain, and plastic strain of the bulk glassy Zr–Al–Co–Nb alloys were 550, 98 GPa, 2100 MPa, 2.9%, and 0.9%, respectively.

Sign in / Sign up

Export Citation Format

Share Document