Showa Aluminum Corporation

Sharp Kabushiki Kaisha Corporation

Ryotatsu Otsuka

Kazuo Toyoda

Shigemi Tanimoto

Koji Ashida

Hideo Shingu

Yuji Asano

Toshiaki Fukuyama

Shoichi Sato

Takashi Tomita

Tohru Nunoi

Masakazu Furuta

Kozo Arai

Kenji Wada

Masashi Sakaguchi

Tomohiro Machida

Kenji Tsukamoto

Yasushi Tashiro

Osamu Watanabe

Jin Zhang

Kohei Itoi

Shigeru Sato

Hideo Yamamoto

Toshio Nishide

Sigemi Tanimoto

The disclosure is directed to a method for purifying metals, which can very efficiently and inexpensively eliminate impurity elements included in various metallic or semiconductor materials, or more specifically included in metallurgical grade silicon.

Method of purifying metal

A first aluminum brazing alloy for cold brazing, comprises 70 to 90% by weight of zinc and 0.05 to 5% by weight of titanium with the balance consisting of aluminum and impurities. A second aluminum brazing alloy for cold brazing, comprises 30 to 70% by weight of zinc, 1 to 7% by weight of silicon, and 0.05 to 5% by weight of titanium with the balance consisting of aluminum and impurities. Brazing alloys having these compositions have a low melting point and can well wet a base metal. Further, use of the above aluminum brazing alloy for cold brazing enables a low-melting aluminum material to be well brazed at 400 to 550&deg; C.

Aluminum brazing alloy for cold brazing and method for brazing low-melting aluminum material

A brazing material that has a low melting point and can braze aluminum materials at a low temperature with a good wetting property is disclosed. The brazing material can include a matrix composed of Zn, a Zn--Al alloy or a Al--Zn--Si alloy having a low melting point each preferably containing 0.001 to 3.0 wt % of rare-earth element. When such a brazing material is used, aluminum materials can be brazed at a temperature of 580.degree. C. or below.

Brazing material for use in a low temperature brazing and method for low

A process for brazing a die-cast aluminum material, wherein a die-cast aluminum material produced at a gate speed of 20 m/s or higher is used to be brazed at a brazing temperature of 500.degree. C. or lower. Further, it is preferred that the die-cast aluminum material is produced under a casting pressure of 600 kgf/cm.sup.2 or lower, or that the die-cast aluminum material is produced while depressurizing a mold. Brazing may as well be conducted using a brazing filler metal material composed of 6 to 24 wt. % of Al and the balance consisting of Zn and impurities. In the foregoing manner, the die-cast aluminum material can be brazed by heating it to a high temperature.

Process for brazing die-cast aluminum material

Objects of the present invention are to provide a brazeable aluminum alloy cast material which can be manufactured brazeable products without lowering the productivity and the method of brazing a cast material. The cast material is composed of: 0.5-4.5% by weight of Mn; 0.5-3% by weight of Si; 0.5-1% by weight of Fe; and the balance composed of aluminum and impurities. In the method of brazing the cast material, a brazing agent and/or flux are used, the brazing agent is composed of: 25-65% by weight of Zn; 2-7% by weight of Si; and the balance composed of aluminum and 0.1% or less of Fe as one of impurities. The flux is a mixture of: 0.5-5% by weight of LiF; 1-10% by weight of ZnCl.sub.2 ; 1-5% by weight of K.sub..alpha. AlF.sub..alpha.+3 (.alpha. is an integer not less than 1.); and the balance composed of BaCl.sub.2 -KCl-NaCl.

Brazeable aluminum alloy cast material and method of brazing the same

A metal purifying apparatus comprises a closed melting furnace equipped with a heater, molten metal holding crucible disposed within the furnace, a vertical hollow rotary shaft penetrating through a top wall of the furnace, a packing sealing off a clearance in the shaft penetrating portion of the top wall around the shaft, rotary drive means for rotatingly driving the shaft, a hollow rotary cooling body fixedly provided at a lower end of the shaft and having an interior space communicating with an interior space of the shaft, and a cooling fluid supply source for supplying a cooling fluid to the interior of the cooling body. The rotary shaft has disposed therein a cooling fluid discharge pipe with a lower end positioned below the top wall of the furnace. An outer periphery of the discahrge pipe and an inner periphery of the shaft are spaced apart from each other and define a space portion providing a cooling fluid supply channel for passing therethrough the cooling fluid to be supplied from the source to the interior space of the cooling body. The discharge pipe has an interior providing a cooling fluid discharge channel for discharging therethrough the cooling fluid supplied to the interior of the cooling body.

Apparatus for purifying metal

A metal having a high purity is prepared by immersing a hollow rotary cooling member in a molten metal containing eutectic impurities and rotating the cooling member while supplying a cooling fluid to the interior of the cooling member, whereby the high-purity metal is caused to crystallize out on a metal deposition area of the peripheral surface portion of the cooling member present under the surface of the molten metal, the metal deposition area being the peripheral surface of at least a part of the entire portion, present under the melt surface, of the member. When the purified metal is caused to crystallize but by rotating the cooling member, a flow of molten metal having a downward velocity component is produced in the vicinity of an upper part of the entire portion, present under the melt surface, of the cooling member.

Method of preparing high-purity metal and rotary cooling member for use

A metal having a high purity is prepared by immersing a hollow rotary cooling member in a molten metal containing eutectic impurities and rotating the cooling member while supplying a cooling fluid to the interior of the cooling member, whereby the high-purity metal is caused to crystallize out on a metal deposition area of the peripheral surface portion of the cooling member present under the surface of the molten metal, the metal deposition area being the peripheral surface of at least a part of the entire portion, present under the melt surface, of the member. When the purified metal is caused to crystallize out by rotating the cooling member, a flow of molten metal having a downward velocity component is produced in the vicinity of an upper part of the entire portion, present under the melt surface, of the cooling member.

An apparatus for treating a molten metal comprises a vertical post, a treating container disposed at one side of the post and having an opening at its upper end for containing the molten metal, a horizontal suspending arm mounted at its base end on the post upwardly and downwardly movably and rotatable in a horizontal plane, a vertical rotary shaft suspended from the arm and having a treating gas channel internally extending therethrough longitudinally, a bubble releasing-dispersing rotor provided at the lower end of the rotary shaft and having in its bottom surface a treating gas outlet in communication with the gas channel, the rotor being movable into and out of the container through the opening, and at least one baffle suspended from the arm and movable into and out of the container through the opening for preventing eddying and waving. When there arises a need to repair or relace the rotary shaft, the rotor and/or the baffle, or when the dross is to be removed from the surface of molten metal after the treatment, the rotor, the shaft and the baffle are brought out of the container by raising the suspending arm and are thereafter brought to a position away from immediately above the container by horizontally moving the arm. The above work is then performed.

Apparatus for treating molten metal

Hydrogen gas and non-metallic inclusions are removed from molten aluminum by a process comprising the steps of rendering the portion above the surface of molten aluminum in a treating vessel where the molten aluminum is placed, an atmosphere of air having a lower dew point than that of the atmosphere and maintaining it as it is, introducing a treating gas into the molten aluminum, and removing floating non-metallic inclusions and treating gas containing hydrogen gas from the surface of the melt.

Process for treating molten aluminum to remove hydrogen gas and

Crude silicon is purified by melting the crude silicon, maintaining the molten silicon above the solidification temperature thereof in an inert gas atmosphere, and rotating a hollow rotary cooling member as immersed in the molten silicon while introducing a cooling fluid into the cooling member to cause high-purity silicon to crystallize on the outer surface of the cooling member.

Process and apparatus for purifying silicon

A device comprising a rotary shaft to be disposed in a liquid substantially vertically and rotatable about its own axis, the rotary shaft having a gas channel extending therethrough axially of the shaft, and a rotor fixed to the lower end of the rotary shaft and having at its bottom surface a gas discharge outlet communicating with the gas channel. The rotor is formed in its bottom surface with radial grooves extending from the gas outlet to the peripheral surface of the rotor and each having an open end at the peripheral surface. A recess is formed in the peripheral surface between the open ends of immediately adjacent grooves and has an open lower end at the bottom surface. When the rotary shaft is rotated in a liquid while supplying a gas to the gas channel of the shaft, the gas flows out from the discharge outlet into the radial grooves and is released from the open ends of the grooves at the peripheral surface into the liquid in the form of finely divided bubbles. The bubbles are diffused through the entire body of the liquid by the liquid flowing in the centrifugal direction while revolving in the same direction as the rotor owing to the agitating action of the recesses in the rotor peripheral surface.

Device for releasing and diffusing bubbles into liquid

Hydrogen gas and non-metallic inclusions are removed from molten aluminum by a process comprising the steps of maintaining an atmosphere containing BF.sub.3 gas in a treating vessel above the surface of molten aluminum placed therein, introducing a treating gas into the molten aluminum, and removing floating non-metallic inclusions and treating gas containing hydrogen gas from the surface of the molten aluminum.

To obtain a high-purity aluminum fraction from aluminum containing both eutectic impurities and peritectic impurities, the contents of these impurities in the original aluminum are reduced by melting the original aluminum to obtain molten aluminum, adding boron to the molten aluminum, and rotating a cooling body as immersed in the boron-containing molten aluminum while introducing a cooling fluid to the interior of the body to crystallize high-purity aluminum on the surface of the body. The peritectic impurities react with the boron to form metallic borides, which are centrifugally forced away from the cooling body by the rotation of the body without being incorporated into the aluminum crystallized on the surface of the body. The eutectic impurities are removed from the crystallized aluminum on the surface based on the principle of segregation.

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Osaka, Japan

Ryotatsu Otsuka