Other

Japan Science and Technology Corporation

Alps Electric Co., Ltd.

Japan Science and Technology Agency

Research Development Corporation of Japan

Gac International, Inc.

Akihisa Inoue

Kabushiki Kaisha Makabe Giken

Tao Zhang

Tsuyoshi Masumoto

Nobuyuki Nishiyama

Akira Takeuchi

Yoshiyuki Shinohara

Mikio Mottate

Kikuo Nishi

Masahide Onuki

Takashi Kaneko

Tetsuo Yamaguchi

Wei Zhang

Eiichi Makabe

Kazuya Sato

Yuzi Ogata

Kei Kurosaka

Yuu Kasori

Xinmin Wang

Hidenobu Nagahama

The present invention provides Cu-base amorphous alloys containing an amorphous phase of 90% or more by volume fraction. The amorphous phase has a composition represented by the formula: Cu(Zr+Hf)Tior Cu(Zr+Hf')TiMT, wherein M is one or more elements selected from Fe, Cr, Mn, Ni, Co, Nb, Mo, W, Sn, Al, Ta and rare earth elements, T is one or more elements selected from the group consisting of Ag, Pd, Pt and Au, and a, b, c and d are atomic percentages falling within the following ranges: 5&#x2266;a&#x2266;55, 0&#x2266;b&#x2266;45, 30&#x2266;a+b&#x2266;60, 0.5&#x2266;c&#x2266;5, 0&#x2266;d&#x2266;10. The Cu-base amorphous alloy has a high glass-forming ability as well as excellent mechanical properties and formability, and can be formed as a rod or plate material with a diameter or thickness of 1 mm or more and an amorphous phase of 90% or more by volume fraction, through a metal mold casting process.

Method of making a Cu-base bulk amorphous alloy

The present invention provides a Cu&#x2014;Be based amorphous alloy comprising an amorphous phase of 50% or more by volume fraction. This alloy has a composition represented by the following formula: CuBe(ZrHfTi). In the formula, 'a' and 'b' represent atomic percentages which are 0&#x3c;a&#x2266;20 and 20&#x2266;b&#x2266;40, and &#x201c;x&#x201d; and &#x201c;y&#x201d; represent atomic fractions which are 0&#x2266;x&#x2266;1 and 0&#x2266;y&#x2266;0.8. The alloy may contain a small amount of one or more elements selected from the group consisting of Fe, Cr, Mn, Ni, Co, Nb, Mo, W, Sn, Al, Ta and rare-earth elements and/or the group consisting of Ag, Pd, Pt and Au. The alloy has a wide supercooled-liquid temperature range and a large reduced glass transition temperature (Tg/Tm) to achieve a high thermal stability against crystallization or a high glass-forming ability.

Cu-Be base amorphous alloy

A Ti&mdash;Zr type alloy manifesting excellent plastic workability at normal temperature fit for the use in general industry, allowing improvement in corrosion resistance fit for the use in medical treatment, offering improved corrosion resistance in an acidic solution, particularly a HCl solution, and having flexibility as evinced by a low Young's modulus on a par with a bone; and a medical appliance such as a guide wire to be directly inserted into a blood vessel of a human body under the X-ray fluoroscopy and a stent retained in a human body for a long time, which are made of the Ti&mdash;Zr type alloy are provided. The Ti&mdash;Zr type alloy of the present invention consists of 25 to 50% by weight of Ti, 25 to 60% by weight of Zr, 5 to 30% by weight of Nb, and 5 to 40% by weight of Ta, provided that the weight ratio of Zr to Ti be in the range of 0.5 to 1.5 and the weight ratio of Nb to Ta be in the range of 0.125 to 1.5. The medical appliance of the present invention comprises a part formed of a Ti&mdash;Zr type alloy which consists of 25 to 50% by weight of Ti, 25 to 60% by weight of Zr, 5 to 30% by weight of Nb, and 5 to 40% by weight of Ta, provided that the weight ratio of Zr to Ti fall in the range of 0.5 to 1.5 and the weight ratio of Nb to Ta fall in the range of 0.125 to 1.5.

Ti-Zr type alloy and medical appliance formed thereof

The present invention intends to provide a production method for a highly reliable bulk metallic glass of a high cold draft of 70% or more, and better post-cold working mechanical properties than those of the metallic glass being cast. The bulk metallic glass is obtained by pressing and expanding an alloy melt of composition capable of being glassified between the cooled upper and lower molds, which are highly heat-conductive water-cooled molds, so as to apply pressure to the melt while it is solidified. Nano-particles are thus dispersed in the amorphous phase of the metallic glass, thereby obtaining a metallic glass with nano-particles dispersed in its amorphous phase. The metallic glass with nano-particles of such a high ductility is further cold worked, for example by rolling to make the final product.

Highly-ductile nano-particle dispersed metallic glass and production method therefor

A zirconium system amorphous alloy having a composition expressed by a general formula Zr Ti Al Cu Ni wherein a, b, X, and Y in the formula represent atomic percentage, and fulfill X<10, Y>5, Y<&minus;(1/2)X&plus;35/2, 15&lE;a&lE;25, and 5&lE;b&lE;15, the zirconium system amorphous alloy has an amorphous phase of more than 50 volume % of the alloy.

Zirconium system amorphous alloy

A molten alloy having an amorphous forming ability is pressure-solidified at a pressure exceeding one atmospheric pressure to eliminate casting defects. The cooling rate during the solidification is adjusted to disperse fine crystals having a mean crystal grain diameter of 1 nm to 50 &mgr;m and a volume percentage of 5 to 40% in an amorphous alloy ingot. In this way, a uniform residual compressive stress is imparted in the amorphous alloy ingot. Furthermore, the amorphous ingot produced by this method can be strengthened by heating it at a constant temperature rising rate to infiltrate at least one of boron, carbon, oxygen, nitrogen and fluorine from the surface of the amorphous alloy ingot in a supercooled liquid state before crystallization, to thereby precipitate a high melting point compound thereof with an element forming the amorphous alloy within the alloy ingot so as to strength the alloy.

Method for producing an amorphous alloy having excellent strength

An amorphous Zr alloy has a composition expressed as Zr&mdash;Al &mdash;Ni &mdash;Cu &mdash;M . M is one or more elements selected from Ti, Nb and Pd. The a, b, c, and d are amounts in atomic %, and satisfy the following formulas. 5&lE;a&lE;0; 30&lE;b&plus;c&lE;50; b/c&lE;1/3; and 0<d&lE;7. The remainder are Zr and inevitable impurities. The alloy contains a non-crystalline phase of 90% or higher by volume. Also, the amorphous alloy indicates an excellent glass-forming ability with a supercooled liquid range over 100&deg; C. (indicated by a difference between the crystallization temperature and the glass transition temperature) and which has a thickness of 1 mm or thicker. Further, it has excellent strength and toughness indicated by the following mechanical characteristics: tensile strength of 1800 MPa or higher; flexural strength of 2500 MPa or higher; Charpy impact value of 100 kJ/m or higher; and fracture toughness value of 50 MPa*m or higher.

High-strength high-toughness amorphous zirconium alloy

A high permeability metal glassy alloy for high frequencies contains at least one element of Fe, Co, and Ni as a main component, at least one element of Zr, Nb, Ta, Hf, Mo, Ti, V, Cr, and W, and B. In the metal glassy alloy, the temperature interval &Dgr;Tx of a super cooled liquid region, which is represented by the equation &Dgr;Tx&equals;Tx&minus;Tg (wherein Tx represents the crystallization temperature, and Tg represents the glass transition temperature) is 20&deg; C. or more, and resistivity is 200 &mgr;&OHgr;&middot;cm or more.

High permeability metal glassy alloy for high frequencies

A molten alloy was pressure-solidified under a pressure exceeding one atmospheric pressure to eliminate casting defects. The molten alloy was solidified by applying a cooling rate difference to the surface and the interior of the molten alloy to allow a compressive stress layer to remain on the surface of the amorphous alloy ingot and a tensile stress layer in the interior portion. Thus, a amorphous alloy sheet having a thickness of 1 mm or more and excellent in bending strength and impact strength is obtained.

Method of producing amorphous alloy excellent in flexural strength and impact strength

The present invention provides an amorphous alloy containing at least one element of Fe, Co, and Ni as a main component, at least one element of Zr, Nb, Ta, Hf, Mo, Ti and V, and B, wherein the temperature width &Dgr;Tx of a supercooled liquid region expressed by the equation &Dgr;Tx&equals;Tx&minus;Tg (wherein Tx indicates the crystallization temperature, and Tg indicates the glass transition temperature) is 20&deg; C. or more. The amorphous alloy has excellent soft magnetic properties and high hardness, and can suitably be used for a transformer, a magnetic head, a tool, etc.

Soft magnetic amorphous alloy and high hardness amorphous alloy and high hardness tool using the same

A high-strength amorphous alloy represented by the general formula: X,M,Al,T,(wherein X is at least one element selected between Zr and Hf; M is at least one element selected from the group consisting of Ni, Cu, Fe, Co and Mn; T is at least one element having a positive enthalpy of mixing with at least one of the above-mentioned X, M and Al; and a, b, c and d are atomic percentages, provided that 25&lE;a&lE;85, 5&lE;b &lE;70, 0<c&lE;35 and 0<d&lE;15) and having a structure comprising at least having an amorphous phase. The amorphous alloy is produced by preparing an amorphous alloy having the above-mentioned composition and containing at least an amorphous phase, and heat-treating the alloy in the temperature range from the first exothermic reaction-starting temperature (Tx,: crystallization temperature) thereof to the second exothermic reaction-starting temperature (Tx,) thereof to decompose the amorphous phase into a mixed phase structure consisting of an amorphous phase and a microcrystalline phase.

High-strength amorphous alloy and process for preparing the same

An alloy material 4 received in a melting hearth 1 is melted by high-density energy supplied from a heat source 5. The molten alloy is transferred to a forced-cooled die 3 having a cavity 2 defining the profile of a product, and quenched to an amorphous state. The alloy has the composition represented by the general formula of Zr.sub.100-a-b-c A.sub.a B.sub.b C.sub.c, wherein the mark A represents one or more elements selected from Ti, Hf, Al and Ga, the mark B represents one or more elements selected from Fe, Co, Ni and Cu, the mark C represents one or more elements selected from Pd, Pt, Au and Ag, and the marks a-c represent the atomic ratios of respective elements A-C under the conditions of a=5-20, b=15-45, c.ltoreq.10 and a+b+c=30-70. The differential temperature region .DELTA.T (=T.sub.x -T.sub.g) in the supercooled liquid phase of the Zr alloy represented by the difference between the crystallization point T.sub.x and the glass transition point T.sub.g is preferably 100 K or more. The obtained amorphous alloy has a rod-shaped or tubular profile having a large cross section and being excellent in plastic workability.

Rod-shaped or tubular amorphous Zr alloy made by die casting and method

A hard magnetic material of the present invention contains Fe as a main component and further contains elements R and L, and B. Not less than 60% of the structure of the hard magnetic material is composed of a fine crystalline phase having an average grain size of not more than 100 nm and the rest is composed of an amorphous phase. The fine crystalline phase essentially consists of bcc-Fe and contains at least R.sub.2 Fe.sub.14 B.sub.1.

Hard magnetic material

The present invention provides an amorphous alloy containing at least one element of Fe, Co, and Ni as a main component, at least one element of Zr, Nb, Ta, Hf, Mo, Ti and V, and B, wherein the temperature width .DELTA.Tx of a supercooled liquid region expressed by the equation .DELTA.Tx=Tx-Tg (wherein Tx indicates the crystallization temperature, and Tg indicates the glass transition temperature) is 20.degree. C. or more. The amorphous alloy has excellent soft magnetic properties and high hardness, and can suitably be used for a transformer, a magnetic head, a tool, etc.

Soft magnetic amorphous alloy and high hardness amorphous alloy and high

Orthodontic appliances in accordance with the present invention are formed from amorphous alloys having a supercooling liquid region. The appliances have high corrosion resistance, high durability and high strength. The appliances are particularly useful when changes and adjustments in the orthodontic state become necessary in the course of orthodontic treatment. The present invention also provides improvements in the base surfaces of orthodontic appliances adapted to be bonded to tooth surfaces. The appliances can consequently be securely affixed to tooth surfaces.

Growing community of inventors

Sendai, Japan

Tao Zhang