Kabushiki Kaisha Toshiba

Toshiba Materials Co., Ltd.

Tomohisa Arai

Keisuke Hashimoto

Shinya Sakurada

Masami Okamura

Takahiro Hirai

Naoyuki Sori

Masashi Sahashi

Takao Sawa

Fumiyuki Kawashima

Takashi Rokutanda

Katsutoshi Nakagawa

Yoichi Tokai

Tadaharu Kido

Takao Kusaka

Hiroyuki Hasebe

Hideki Nakagome

Shusuke Inada

Takamichi Inaba

Akihiko Tsutai

Toshiya Sakamoto

Noriaki Sato

Yoshitaka Yanagita

Nobuyoshi Jimbo

Rohana Chandrtilleke

Nobuo Uchida

Seiki Sato

There are provided a high hardness, high corrosion resistance and high wear resistance alloy, wherein the alloy is an aging heat treated Cr(chromium)-Al(aluminum)-Ni(nickel)-base alloy, the proportion of a mixed phase of (&#x3b1; phase+&#x3b3;' phase+&#x3b3; phase) precipitated at grain boundaries of &#x3b3; phase grains in a metal structure in the cross section of the alloy is not less than 95% in terms of area ratio, and the intensity ratio as measured by X-ray diffractometry of the alloy is not less than 50% and not more than 200% in terms of I&#x3b1;(110)/[I&#x3b3;(200)+I&#x3b3;&#x2032;(004)]&#xd7;100, and a component comprising this alloy, a material for an alloy which can form this alloy, and a process for producing this alloy. The present invention can provide a Cr&#x2014;Al&#x2014;Ni-base alloy possessing excellent corrosion resistance, hardness, wear resistance, releasability, fatigue strength, and planishing property in a molding face, a component comprising this alloy, a material for an alloy which can form this alloy, and a process for producing this alloy.

High hardness, high corrosion resistance and high wear resistance alloy

A cutter is composed of a Ni&#x2014;Cr alloy containing from 32 to 44 mass percent of Cr, from 2.3 to 6.0 mass percent of Al, the balance being Ni, impurities, and additional trace elements and having a Rockwell C hardness of 52 or more. This Ni&#x2014;Cr alloy provides a cutter produced with a superior workability and by a significantly simplified process, having a low deterioration in the hardness even when heated in use, having excellent corrosion resistance and low-temperature embrittlement resistance, and satisfactorily maintaining the cutting performance for a long time.

Cutter composed of Ni-Cr alloy

A cutter is composed of a Ni&#x2014;Cr&#x2014;Al alloy containing from 32 to 44 mass percent of Cr, from 2.3 to 6.0 mass percent of Al, the balance being Ni, impurities, and additional trace elements and having a Rockwell C hardness of 52 or more. This Ni&#x2014;Cr&#x2014;Al alloy provides a cutter produced with a superior workability and by a significantly simplified process, having a low deterioration in the hardness even when heated in use, having excellent corrosion resistance and low-temperature embrittlement resistance, and satisfactorily maintaining the cutting performance for a long time.

Cutter composed of Ni-Cr-Al Alloy

A bond magnet comprises a molded body in which a mixture of flake of magnet material comprising rare earth element-iron-nitrogen as main component, TbCu type crystal phase as a principal phase and a thickness of less than 200 &mgr;m a binder is compression molded. A compression molded body constituting a bond magnet has a density of 6&times;10 kg/m or more. In the step of compression molding a mixture of magnet material and binder, pressure is applied a plurality of times, or pressure is applied while rotating a punch and die, or the binder is cured while applying pressure to obtain such a bond magnet with good reproducibility. Such a bond magnet has excellent magnetic properties and corrosion resistance.

Bond magnet and manufacturing method thereof, and actuator therewith

A cold accumulating material comprising a number of magnetic particles mainly composed of oxide, wherein an average value of equivalent circle diameters of crystal grains constituting the magnetic particles is 0.3-20 &mgr;m. It is preferable that an area ratio of the crystal grains each having an equivalent circle diameter of 50 &mgr;m or more is 10% or less with respect to whole crystal grains constituting the magnetic particle. According to the above structure, there can be provided a cold accumulating material which is free from being finely pulverized, and is excellent in thermal shock resistance and durability, and capable of exhibiting a significant refrigerating performance at low temperature range for a long period of time in a stable condition.

Cold accumulating material, method of manufacturing the same and refrigerator using the material

Magnet powder has a composition expressed by (R R B T ) N (in formula, R is at least one kind of element selected from rare earth elements, R is at least one kind of element selected from Zr, Hf and Sc, T is at least one kind of element selected from Fe and Co, and X, Y, Z and Q are numbers satisfying 2 atomic %&lE;X, 0.01 atomic %&lE;Y, 4&lE;X&plus;Y&gE;20 atomic %, 0&lE;Z&lE;10 atomic %, and 0.1&lE;Q&lE;20 atomic %, respectively), and TbCu crystal phase as a principal phase. In such magnet powder, a ratio of fine particles of which maximum diameter is 22 &mgr;m or less is 20% by weight or less. Alternatively, surface roughness of particles constituting the magnet powder is 5 &mgr;m or less in terms of maximum height R provided in JIS B 0601-1994. Accordingly, to such a magnet powder, excellent magnetic properties can be obtained with reproducibility.

Magnet powder and method for producing the same, and bonded magnet using the same

A regenerator comprises a regenerator body and cold accumulating material packed in the regenerator body in which cooling medium gas flows from one end portion of the regenerator body to the other end portion of the regenerator body so as to obtain a lower temperature, wherein at least part of the cold accumulating material is a plate-shaped cold accumulating material having a thickness of 0.03-2 mm. In the above structure, it is preferable that the cold accumulating material is composed of an alloy containing 10 at % or more of rare earth element and that a length of the plate-shaped cold accumulating material in a flowing direction of the cooling medium gas is 1-100 mm. According to the above structure, there can be provided a regenerator (cold accumulating unit) and a refrigerator using the regenerator which is free from being finely pulverized, and is excellent in workability and durability, and capable of exhibiting a significant refrigerating performance at low temperature range for a long period of time in a stable condition.

Regenerator and cold accumulation refrigerator using the same

Magnetic material and manufacturing method thereof, and bonded magnet using the same

A magnetic material essentially consists of a composition represented by general formula: R R B N H M (in the formula, R denotes at least one kind element selected from rare earth elements, R denotes at least one kind element selected from Zr, Hf and Sc, M denotes at least one kind element selected from Fe and Co, X, Y, Z, U and V are numbers satisfying 2 at. %&lE;X, 0.01 at. %&lE;Y, 4&lE;X&plus;Y&lE;20 at. %, 0&lE;Z&lE;10 at. %, 0.1&lE;U&lE;18 at. %, 0.01&lE;V&lE;10 at. %, respectively), and comprises a TbCu type crystal phase as a principal phase. A nitriding treatment to a mother alloy is carried out in a mixed gas of ammonia gas and hydrogen gas of which partial pressure ratio is set in the range of 3<P /P when partial pressure of ammonia gas is P , that of the hydrogen gas is P . According to such a nitriding treatment, without hindering rapid absorption of nitrogen by a mother alloy of which principal phase is a TbCu type crystal phase, deterioration of magnetic characteristics due to too much absorption of nitrogen can be suppressed.

A cold accumulating material comprises a set of particulate cold accumulating substances, pores formed between the particulate cold accumulating substances, and a binder for mutually binding the particulate cold accumulating substances, wherein a porosity of the cold accumulating material is 15-70 vol %. A median diameter of the pores existing in the cold accumulating material is preferably set to 10-300 &mgr;m. An oxygen concentration at an area ranging from a surface of the particulate cold accumulating substance to a portion having a depth of 100 angstroms (A) from the surface is preferably set to 5-80 at %. According to the above structure, there can be provided a cold accumulating material and a refrigerator using the cold accumulating material which is free from being finely pulverized, and has a high mechanical strength, and capable of exhibiting a significant refrigerating performance at low temperature range for a long period of time in a stable condition, and which can be mass-produced with a high production yield and low cost.

Cold accumulating material and cold accumulation refrigerator using the same

Cold-accumulating material and cold-accumulating refrigerator using the same

A bond magnet comprises a molded body in which a mixture of flake of magnet material comprising rare earth element-iron-nitrogen as main component, TbCu,type crystal phase as a principal phase and a thickness of less than 200 &mgr;m a binder is compression molded. A compression molded body constituting a bond magnet has a density of 6&times;10,kg/m,or more. In the step of compression molding a mixture of magnet material and binder, pressure is applied a plurality of times, or pressure is applied while rotating a punch and die, or the binder is cured while applying pressure to obtain such a bond magnet with good reproducibility. Such a bond magnet has excellent magnetic properties and corrosion resistance.

Cold accumulating material for extremely low temperature cold,

A permanent magnet material has a principal phase of TbCu7 type crystal structure and improved magnetic properties. This permanent magnet material is represented by the general formula: R1.sub.x R2.sub.y B.sub.z N.sub.u M.sub.100-x-y-z-u, wherein R1 is at least one rare earth element including Y, R2 is at least one element selected from the group consisting of Zr, Hf and Sc, M is at least one element selected from Fe and Co, x, y, z and u are atomic percents individually defined as x.gtoreq.2, y.gtoreq.0.01, 4.ltoreq.x+y.ltoreq.20, 0.ltoreq.z.ltoreq.10, and 0&lt;u.ltoreq.20. The permanent magnet material has a principal phase of a TbCu.sub.7 type crystal structure. The permanent magnet material satisfies the relation of t.ltoreq.60 and .sigma./t.ltoreq.0.7, wherein t(nm) is an average crystal grain size of the principal phase and .sigma.(nm) is a standard deviation of the crystal grain size.

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Yokohama, Japan

Tomohisa Arai