Sumitomo Chemical Company, Limited

The Texas A&m University System

Other

Akihiko Takahashi

Hitoshi Yasuda

Hiroshi Tabuchi

Karl T Hartwig

Lacy Clark McDonald

Masahiro Hasegawa

Ichiro Tanaka

Hong Zou

Shinji Fujiwara

Kenichi Kikuchi

Genzo Iwaki

Hidemitsu Shimizu

Noriyuki Tatsumi

Fumikazu Hosono

Hidezumi Moriai

A method for purifying aluminum to provided which comprises the steps of maintaining aluminum as a starting material in a molten condition in N&plus;1 vessels; wherein N&plus;1 vessels for molten aluminum and N cooling bodies are provided which are immersed in molten aluminum in the vessels and upon which highly purified aluminum is crystallized on the surfaces thereof. The N&plus;1 vessels are arranged sequentially from 1-st to (N&plus;1)-th and the N cooling bodies are sequentially arranged from 1-st to N-th, respectively, and the vessels and cooling bodies are moved relative to each other.

Method for purifying aluminum

A tube made of oxygen free copper is filled with a plurality of copper matrix Nb&mdash;Ti superconducting lead wires to obtain a composite billet. The resulting billet is subjected to hydrostatic pressure extrusion. Further, ageing heat treatment and wire drawing process are repeated for the composite material three times to prepare a Cu/Nb&mdash;Ti superconducting single wire. Then, the resulting Cu/Nb&mdash;Ti superconducting single wires are stranded each other to produce a superconducting strand. The superconducting strand is coated with an aluminum alloy to which either a content of 20 to 100 ppm of Cu and Mg or Mg, or a content of 10 to 120 ppm of Si and Cu is added by means of hot extrusion, the strand thus extruded is reduced by 0 to 20% in accordance with cold working to produce an aluminum stabilized superconductor. As a result, such aluminum stabilized superconductor having high mechanical strength as well as good thermal and electrical stability is provided while achieving light weight and downsizing thereof.

Aluminum stabilized superconductor with Cu and Mg

The present invention provides a method for producing high purity aluminum by immersing a cooling body in molten aluminum, and forming and growing crystals of the high purity aluminum on the cooling body by rotating the cooling body and introducing bubbles of a gas into the rotating molten aluminum by the rotation of the cooling body.

Method for producing high purity aluminum

The present invention provides a method for producing high purity aluminum by immersing a cooling body in molten aluminum, and forming and growing crystals of the high purity aluminum on the cooling body by rotating the molten aluminum around the cooling body and introducing bubbles of a gas into the rotating molten aluminum.

A sputtering target of a single crystal aluminum alloy which has a uniform concentration distribution of an added metal element and a controlled crystal orientation is prepared using a continuous casting apparatus equipped with a starting rod by solidifying a melt of aluminum having a purity of at least 99.9 wt. % which contains 0.1 to 3.0 wt. % of at least one metal element selected from the group consisting of elements having atomic numbers of 3 to 83, at a casting temperature of 670 to 850.degree. C. at a casting rate of 1 to 80 mm/min. in one direction with maintaining an angle between a center axis of a continuous casting mold and a direction of pulling a casting material at 2 degrees or less.

Sputtering target of single crystal aluminum alloy and method for

A sputtering target of a single crystal aluminum alloy which has a uniform concentration distribution of an added metal element and a controlled crystal orientation is prepared using a continuous casting apparatus equipped with a starting rod by solidifying a melt of aluminum having a purity of at least 99.9 wt. % which contains 0.1 to 3.0 wt. % of at least one metal element selected from the group consisting of elements having atomic numbers of 3 to 83, at a casting temperature of 670 to 850.degree. C. at a casting rate of 1 to 80 m/min. in one direction with maintaining an angle between a center axis of a continuous casting mold and a direction of pulling a casting material at 2 degrees or less.

Sputtering target of single crystal aluminum alloy

A metal matrix composite comprising 2 to 80 volume % of .alpha.-alumina powder as a reinforcement, said .alpha.-alumina powder comprises polyhedral primary particles substantially having no fracture surface, D50 of .alpha.-alumina powder is 0.1 .mu.m to 50 .mu.m and a ratio of D50 to D10 is not more than 2, wherein D10 and D50 are particle sizes at 10% and 50% cumulation from the smallest particle side of a weight cumulative particle size distribution, respectively, and a process for producing the metal matrix composite which comprises infiltrating a molten metal into the .alpha.-alumina powder under pressure or non-pressure.

Metal matrix composite and process for producing the same

The present invention concerns an aluminum alloy conductor of a cryostatic stabilizer for use at ultra low temperatures of 30.degree. K. or lower which is provided on and around a superconductor. The aluminum alloy conductor is made of 6 to 200 weight ppm of at least one element selected from the group of metallic and semimetallic effective elements consisting of B, Ca, Ce, Ga, Y, Yb and Th, and aluminum and inevitable impurities. The aluminum alloy conductor is obtained by adding at least one of these elements into a high purity aluminum whose purity is at least 99.98 wt. %. The aluminum alloy conductor has a 0.2% proof strength of not greater than 2.6 Kg/mm.sup.2.

High purity aluminum alloy conductor for use at ultra low temperatures

A method for manufacturing an aluminum alloy conductor for use at ultra low temperature which involves the steps of adding at least one of the metallic and semimetallic effective elements selected from the group consisting of B, Ca, Ce, Ga, Y, Yb and Th, in a total amount of 6 to 200 weight ppm, into a previously prepared molten high purity aluminum having a purity of not less than 99.98 wt % to thereby obtain a molten metal mixture; casting the molten metal mixture to thereby obtain a casting; subjecting the casting to extrusion working at 150.degree. C. to 350.degree. C. in an area reduction ratio of 1:10 to 1:150 whereby an extrusion worked product is formed; and annealing the extrusion worked product at a temperature of 250.degree. C. to 530.degree. C. for 3 to 120 minutes, whereby an aluminum alloy conductor for use at ultra low temperature is obtained.

Method of manufacturing a micro-alloy high purity aluminum conductor for

The aluminum conductor having increase of its electric resistivity kept small at ultra low temperature of 30.degree. K. or lower even after cyclic strain is given at ultra low temperature, by controlling the crystal structure of the high purity aluminum conductor with purity of 99.9-99.9999 wt % so as to consist of (i) a veritable single or a substantially single crystal consisting of a bundle of sub-grains which have their crystal axes in the same direction or in the directions within a couple of degrees of deviation as a whole which has a specific crystal axis of &lt;111&gt; or &lt;100&gt; or the crystal axes close thereto in the longitudinal direction of the aluminum conductor, or (ii) a polycrystal most of which grains have respective specific crystal axes of &lt;111&gt; and/or &lt;100&gt;, or the crystal axes close thereto with respect to each grain in the longitudinal direction of the aluminum conductor, and have specific grain size of 0.01 mm to 3.0 mm.

Method for making a high purity aluminum conductor used at ultra low

A process of producing a powder of a transition-metal boride includes producing metal boride particles in a molten metal by contacting a molten salt, to which at least one boron compound was added, with the molten metal containing a transition-metallic element selected from the Groups IV and V of the Periodic Table at an atomic ratio of elemental boron to transition-metallic element from 0.5 to 4.0, while maintaining a contact temperature which is not lower than the melting point of the molten metal and which is less than 1000.degree. C., and recovering the particles from the molten metal. According to the present invention, fine powders of the transition-metal boride which contain few agglomerated particles may be easily obtained using relatively inexpensive feed materials, such as the boron oxides, at a low temperature less than 1000.degree. C. without the necessity of a grinding step.

Process for producing powders of transition metal boride

The aluminum conductor having increase of its electric resistivity kept small at ultra low temperature of 30.degree. K. or lower even after cyclic strain is given at ultra low temperature, by controlling the crystal structure of the high purity aluminum conductor with purity of 99.9-99.9999 wt %. The crystal structure consist of (i) a veritable single or a substantially single crystal consisting of a bundle of sub-grains which have their crystal axes in the same direction or in the directions within a couple of degrees of deviation as a whole which has a specific crystal axis of &lt;111&gt; or &lt;100&gt; or the crystal axes close thereto in the longitudinal direction of the aluminum conductor, or (ii) a polycrystal most of which grains have respective specific crystal axes of &lt;111&gt; and/or &lt;100&gt;, or the crystal axes close thereto with respect to each grain in the longitudinal direction of the aluminum conductor, and have specific grain size of 0.01 mm to 3.0 mm.

High purity aluminum conductor used at ultra low temperature

Polyhedral .alpha.-alumina particles having a particle size on the order of a micrometer and high purity are prepared by maintaining a compression molded aluminum material having, on its surface, a binary compound of aluminum and oxygen atoms or a ternary compound of aluminum, oxygen and hydrogen atoms in an aluminum melt.

Process for preparaing polyhedral .alpha.-alumina particles

Disclosure is a method for producing a cryostatic stabilizer composed of high-purity aluminum which comprises extruding the high-purity aluminum at an extrusion temperature of 250.degree. to 500.degree. C., an extrusion speed of not more than 20 m/min and an extrusion ratio of 10 to 150 by using an extruding machine equipped with a cylindrical die having helical grooves or projections on the inner surface. The method is industrially advantageous.

Method for producing a cryostatic stabilizer

Aluminum bar having a helical contour continuously cast using a mold comprising a heating unit and a cooling unit which have a groove or protrusion helically cut on the inner wall surface, and casting aluminum while conducting rotation and withdrawing in conformity with the slope of the helix.

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Ryugasaki, Japan

Akihiko Takahashi