金属ガラス・無機材料接合開発共同研究プロジェクト

井上 明久

【構成員】

プロジェクトリーダー ユニバーシティ・プロフェッサー：井上 明久

准教授： 張 偉、福原 幹夫、Dmitri V.LOUZGUINE (～2007.11／2007.12～ WPI 兼任教授)、木村 久道 （兼）、

山浦 真一 （兼）

客員教授： 王 新敏、吉村 昌弘

助 教： 羌 建兵、張 慶生 (～2008.11/2008.12～ WPI 助教)、和田 武、謝 国強、関 一郎、Parmanand SHARMA、

久保田 健 （兼）

特別教育研究教員： 吉田 肇、秦 風香、孫 根洙、川嶋 朝日、松浦 眞 技術補佐員： ［2 名］／ 事務補佐員 ［4 名］

【研究成果】

平成17年度東工大の応用セラミックス研究所、大阪大学の接合科学研究所と連携で「金属ガラス・無 機材料接合開発協同研究プロジェクト」がスタートした。平成20年度は金研では、目下三大学の連携 研究において金属ガラスの創製と構造解析が研究の中心として目標進行中である。

Ref. 1-1

W. Zhang, Q.S. Zhang and A. Inoue

Fabrication of Cu-Zr-Ag-Al glassy alloy samples with a diameter of 20 mm by water quenching

J. Mater. Res., 23, (2008), 1452-1456.

Abstract

Cu84−xZrxAg8Al8 (x= 42 to 50 at.%) alloys exhibited extremely high GFA, and full glassy alloy rods with diameters above 12.0 mm were obtained. The best GFA was obtained for the Cu36Zr48Ag8Al8

alloy, and the glassy sample critical diameter achieved by injection copper mold casting and water quenching without flux was over 20 mm. The unusual GFA of this alloy was attributed to the deep eutectic composition, at which solidification occurs via homogeneous nucleation and limited growth rate of the nuclei.

Ref. 1-2

Wei Zhang, Fei Jia, Xingguo Zhang, Guoqiang Xie, Hisamichi Kimura and Akihisa Inoue Two-stage-like glass transition and the glass-forming ability of a soft magnetic Fe-based glassy alloy

J. Appl. Phys., 105, (2009), 053518-1-4.

Abstract

The structure, thermal stability, and crystalline behavior of (Fe0.9Co0.1)67.5Nb4Gd3.5B25 glassy alloy, which exhibits a two-stage-like glass transition phenomenon, were investigated using x-ray diffraction, transmission electron microscopy, and differential scanning calorimetry. The nanoscale metastable (Fe,Co)23B6 phase precipitated in the glassy matrix after annealing, while the two-stage-like glass transition disappeared, indicating the two-stage-like glass transition results from the overlap of the endothermic reaction for the glass transition with the exothermic reaction for the formation of the (Fe,Co)23B6 phase in the supercooled liquid region. The (Fe0.9Co0.1)67.5Nb4Gd3.5B25 glassy alloy exhibits high glass-forming ability, enabling the formation of glassy alloy rods with diameters exceeding 3.0 mm, rather high saturation magnetization of 0.91 T, low coercive force of 2.5 A/m, and high fracture strength of 3870 MPa.

Ref. 2-1

Mikio Fukuhara and Akihisa Inoue

Room temperature Coulomb oscillation of a proton dot in Ni-Nb-Zr-H Glassy alloys with nanofarad capacitance

J. Appl. Phys., 105, (2009), 063715-1-5.

Abstract

A dc current-induced voltage oscillation was observed at room temperature in (Ni36Nb24Zr40)90.1H9.9

glassy alloy ribbons of about 1-mm width and 30-μm thickness and an electrode distance of 20 mm. The I-V characteristic provided evidence of the Coulomb staircase at ^~300 K, suggesting the existence of macroscopic proton dot tunneling along the Zr (Nb)-H-□-H-Zr (Nb) atomic bond array, where □ is the vacancy barrier among clusters. The frequency decreased remarkably with increasing capacitance (C) and resistance (R) at room temperature. Thus the (Ni36Nb24Zr40)90.1H9.9

glassy alloy can be regarded as a dc/ac converting device with a large number of nF capacitance.

Ref. 2-2

M. Fukuhara, H. Abe, H. Nishikawa, T. Takemoto, G. Xie & A. Inoue Amorphous/crystalline transition of copper at room temperature Chem. Phys. Lett., 469, (2009), 289-292.

Abstract

When a glassy alloy Cu60.6Zr29.4Ti10.0 ribbon was immersed in weak acid HF solution at room temperature, selective complete leaching out of the Zr and Ti elements occurred, resulting in the formation of a self-organized crystalline copper ribbon with grain size of 32 nm, by accelerated self-diffusion of Cu. Since the glassy alloy is formed by spd hybridization bonding, based on a combination of valence electrons (Eg) that exceeds the electrons (Ec) predicted by crystalline metallic bond theory, disappearance of its extra valence electrons, i.e., ΔE (Eg - Ec = 0.24 eV) for copper, due to leach-out of the Zr and Ti elements, facilitates on crystallization of the copper

agglomerate.

Ref. 3-1

S.L. Zhu, X.M. Wang, A. Inoue

Glass-forming ability and mechanical properties of Ti-based bulk glassy alloys with large diameters of up to 1 cm

Intermetallics, 16, (2008), 1031-1035.

Abstract

Ti-Zr-Cu-Pd-Sn bulk glass alloys have been synthesized by copper mold casting. The thermal properties. glass-forming ability (GFA) and mechanical properties were examined by differential scanning calorimetry (DSC). differential thermal analysis (DTA). X-ray diffractometry (XRD) and compression test. The series of bulk glassy alloys is expected to be used as biomedical materials because of the absence of toxic elements such as Ni. Al and Be. The 10mm rods with full glassy structure an be obtaind for the Ti40Zr10Cu34Pd14Sn2 and Ti40Zr10Cu32Pd14Sn4 alloys by copper mold casting. The Ti40Zr10Cu36-xPd14Snx(x＝0,2,4,6) glassy alloys have a large supercooled liquid region of over 50K. The Ti40Zr10Cu34Pd14Sn2 bulk glassy alloy exhibits good plasticity of 3.5% during compressive applied load at Ambient temperature in conjunction with distinct yield strain of 2.2%

and high fracture strength of about 2050MPa Ref. 3-2

F.X. Qin, X.M. Wang, G.Q. Xie, A. Inoue

Distinct plastic strain of Ni-free Ti-Zr-Cu-Pd -Nb bulk metallic glasses with potential for biomedical applications

Intermetallic, 16, (2008), 1026-1030.

Abstract

(Ti40Zr10Cu34Pd14)100-xNbx(x=1, 3, 5 at%) bulk metallic glasses containing nano-particles exhibited ultrahigh strength and distinct plastic strain. The yield strength exceeding 2050MPa, young’s modulus of about 80 GPa and the plastic strain of over 6.5% were obtained for 1% and 3%Nb-added alloys due to the suppression of the propagation of shear bands by nano-particles in situ formed in the glassy matrix. The developed Ni-free Ti-based bulk metallic glasses with low Young’s modulus and good mechanical properties are promising candidates for application as artificial dental root materials and other biomaterials

Ref. 4-1

Dmitri V. Louzguine-Luzgin, Kostas Georgarakis, Alain R. Yavari, Gavin Vaughan, Guoqiang Xie, Akihisa Inoue

Effect of Ag addition on local structure of Cu–Zr glassy alloy J. Mater. Res., 24, (2009), 274-278.

Abstract

The effect of Ag substituting Cu on the structural features of the Cu55Zr45, Cu45Zr45Ag10, and Cu35Zr45Ag20 glassy alloys was studied using the real-space pair distribution and radial distribution functions. The experimental x-ray diffraction data obtained in a synchrotron beam were used to derive pair and radial distribution functions through Fourier transformation processing. These results suggest that a certain degree of medium-range order in this alloy is maintained up to about 2.5 nm distance. It is suggested that the addition of Ag causes formation of a more homogeneous local atomic structure compared with that of a binary Cu–Zr alloy, which could be considered as a reason for the improved glass-forming ability of this alloy.

Ref. 4-2

D. V. Louzguine-Luzgin, A. Vinogradov, A. R. Yavari, S. Li, G. Xie, A. Inoue On the deformation and fracture behaviour of a Zr-based glassy alloy Philosophical Magazine, 88, (2008), 2979-2987.

Abstract

The deformation behaviour of Zr60Cu16Ni14Al10 glassy alloy was found to exhibit cleavage-like fracture relief paired with typical vein patterns. The mirror-like cleavage area fraction is found to be comparable with that of vein areas. These two types of patterns alternate on the fracture surface in a direction normal to shear deformation. The structure of the studied alloy was characterised by X-ray diffractometry and scanning and transmission electron microscopy. A small volume fraction of crystals in the form of eutectic colonies were found here and there in the specimen. No distinct difference in the glassy structure of the cleavage-like fracture areas and the areas corresponding to vein patterns was found within the resolution of experimental techniques employed.

Ref. 5-1

Takahiro Okuno, Asahi Kawashima, Hiroaki Kurishita, Wei Zhang, Hisamichi Kimura and Akihisa Inoue

Influences of Temperature and Strain Rate on Mechanical Behavior of a Cu45Zr45Al5Ag5

Bulk Glassy Alloy

Materials Transactions, 49, (2008), 513-517.

Abstract

Since the invention of bulk glassy alloys, a number of studies have been performed at ambient temperatures or above. However, little is known about mechanical properties of bulk glassy alloys at cryogenic temperatures. In this study, we investigated the effects of temperature and strain rate on the mechanical properties of a Cu45Zr45Al5Ag5 bulk glassy alloy fabricated by high pressure die casting methods. Compression tests were performed for the Cu45Zr45Al5Ag5 bulk glassy alloy rods with a diameter of 3 mm at temperatures of 298,

223, 173 and 77 K and at strain rates from 5 x 10^-5 to 5 x 10^-3 s^-1. It is found that the maximum compressive stress and plastic strain to failure increase monotonically with decreasing testing temperature. Multiple shear bands are observed on the side surface of the specimen deformed plastically at cryogenic temperatures. The maximum compressive stress and plastic strain are almost independent of strain rate. The reason for the changes in the maximum compressive stress and plastic strain with temperature and strain rate is discussed.

Ref. 5-2

P. Sharma, H. Kimura and A. Inoue

Magnetic behavior of co-sputtered FeZr amorphous thin films exhibiting perpendicular magnetic anisotropy

Physical Review B, 78, (2008), 134414.

Abstract

Excellent mechanical properties of amorphous/glassy metals along with the capability to fabricate sub -50 nm patterns promise their application as a futuristic material for production of various nano/micro-electromechanical systems. In addition to their applications, these materials pose a lot of challenges in understanding their fundamental properties because of their random structure and involvement of three or more different kinds of atoms. The amorphous FeZr system which is reported to exhibit superconductivity, ferromagnetism, spin glass and antiferromagnetism is an ideal system to understand. The controversial magnetic properties of this system are still a subject of debate. In the present paper we revisited FeZr system and studied their detailed magnetic properties in the temperature range of 5 to 330K.

FexZr100-x (x = 63, 68, 76, 86, 92 and 93 atomic %) thin films were deposited on silicon (100) substrate by a co-sputtering technique. The Curie temperature (Tc) is shown to increase almost linearly with an increase in Fe concentration, but it decreases rapidly for the Fe rich films. The films with x up to ~ 86 at.% have a strange shape of the hysteresis loop and are shown to exhibit perpendicular magnetic anisotropy with a stripe domain structure.

Hysteresis loop shapes are correlated with the magnetic structure of the films, and provide an easy understanding of magnetic properties. It has been shown that the Fe rich films are composed of antiferromagnetic Fe clusters which are embedded in the ferromagnetic amorphous FeZr.

【Representative Publications】

Ref. 1-1 W. Zhang, Q.S. Zhang and A. Inoue

Fabrication of Cu-Zr-Ag-Al glassy alloy samples with a diameter of 20 mm by water quenching

J. Mater. Res., 23, (2008), 1452-1456.

Ref. 1-2 Wei Zhang, Fei Jia, Xingguo Zhang, Guoqiang Xie, Hisamichi Kimura and Akihisa Inoue

Two-stage-like glass transition and the glass-forming ability of a soft magnetic Fe-based glassy alloy

J. Appl. Phys., 105, (2009), 053518-1-4.

Ref. 2-1 Mikio Fukuhara and Akihisa Inoue

Room temperature Coulomb oscillation of a proton dot in Ni-Nb-Zr-H Glassy alloys with nanofarad capacitance

J. Appl. Phys., 105, (2009), 063715-1-5.

Ref. 2-2 M. Fukuhara, H. Abe, H. Nishikawa, T. Takemoto, G. Xie & A. Inoue Amorphous/crystalline transition of copper at room temperature Chem. Phys. Lett., 469, (2009), 289-292.

Ref. 3-1 S.L. Zhu, X.M. Wang, A. Inoue

Glass-forming ability and mechanical properties of Ti-based bulk glassy alloys with large diameters of up to 1 cm

Intermetallics, 16, (2008), 1031-1035.

Ref. 3-2 F.X. Qin, X.M. Wang, G.Q. Xie, A. Inoue

Distinct plastic strain of Ni-free Ti-Zr-Cu-Pd -Nb bulk metallic glasses with potential for biomedical applications

Intermetallic, 16, (2008), 1026-1030.

Ref. 4-1 Dmitri V. Louzguine-Luzgin, Kostas Georgarakis, Alain R. Yavari, Gavin Vaughan, Guoqiang Xie, Akihisa Inoue

Effect of Ag addition on local structure of Cu–Zr glassy alloy J. Mater. Res., 24, (2009), 274-278.

Ref. 4-2 D. V. Louzguine-Luzgin, A. Vinogradov, A. R. Yavari, S. Li, G. Xie, A. Inoue On the deformation and fracture behaviour of a Zr-based glassy alloy Philosophical Magazine, 88, (2008), 2979-2987.

Ref. 5-1 Takahiro Okuno, Asahi Kawashima, Hiroaki Kurishita, Wei Zhang, Hisamichi Kimura and Akihisa Inoue

Influences of Temperature and Strain Rate on Mechanical Behavior of a Cu45Zr45Al5Ag5

Bulk Glassy Alloy

Materials Transactions, 49, (2008), 513-517.

Ref. 5-2 P. Sharma, H. Kimura and A. Inoue

Magnetic behavior of co-sputtered FeZr amorphous thin films exhibiting perpendicular magnetic anisotropy

Physical Review B, 78, (2008), 134414.

【研究計画】

「環境・エネルギー材料開発」、「エレクトロニクス材料開発」、「高度生体材料創製」、「ナノ構造界面 制御接合プロセス」、「異材ナノ界面高機能化」の5 分野につき東工大の応用セラミックス研究所、大 阪大学の接合科学研究所と連携で協同研究がスタートした。現在、これら５分野で三大学を横断した 連 携 研 究 が 強 力 に 進 行 中 で あ る 。2008 年 12 月 10－12 日 に は 三 大 学 連 携 と す る 国 際 会 議

（IUMRS-ICA2008）が名古屋国際会議場で催され、アジア研究教育拠点の金属ガラスワークショッ プが10月17、18日に韓国 東海岸Daemung Sol Beach で開催され、3大学公開討論会が東北大学片 平さくらホール（3月13日）で108人の参加において成功裏に終了した。上記と平行して、5分野別 の三大学連携の会議がもたれ、交互の情報交換、試料供試がなされた。

（1）「環境・エネルギー材料開発」（張 偉 准教授リーダー）

新型の高い安定性を示す水素分離用金属ガラスおよびその複合材料の創製、その水素透過性質の 評価と解明を行う。接合により水素分離用金属ガラスの大寸法化を実現し、ユニークな特性を示 す新しいバルク金属ガラスの開発をする。

（2）「エレクトロニクス材料開発」（福原幹夫 准教授リーダー）

金属ガラスの沸酸中の常温選択腐食によりナノ結晶銅の折出化に成功した。水素含有金属ガラス を素子として用いた実装電子回路において常温における直流→交流増幅作用を確認したので、引 き続いて整流作用、メモリー効果等の確認を行う。

（3）「高度生体材料創製」（王 新敏 客員教授リーダー）

Ni を含まないTi 基生体用金属ガラスの開発に成功した。さらに、金属ガラス合金の表面に

生体活性膜を接合できることを確認。この新規なTi 基金属ガラス材料を用いて人工歯根、人 工指関節などの人工器官への応用研究を行う。

（4）「ナノ構造界面制御接合プロセス」（D. V. Louzguine 教授（兼）リーダー）

各種金属ガラス及び金属ガラス/結晶質、金属ガラス/金属ガラス複合材料の構造、機械的性質、物 理的性質、熱的安定性、結晶化挙動などを検討した。また、放電プラズマ焼結法による高強度大 寸法バルク金属ガラス及びその複合材料を作製したので、焼結体の上記性質及び粒子間接合界面 の微細構造も検討する。

（5）「異材ナノ界面高機能化」（木村久道 准教授（兼）リーダー）

接合に重要な金属ガラスの熱的・機械的・磁気的性質の解明とこれらの知見に基づいて他分野と 連携して金属ガラスが結晶化することなく大寸法形状化できる接合技術の確立を行う。