Daido Tokushuko Kabushiki Kaisha

The Research Institute for Iron, Steel and Other Metals of the Tohoku

The Foundation: the Research Institute for Special Inorganic Materials

Makoto Saito

Sadayuki Nakamura

Atsuyoshi Kimura

Norio Yoshikawa

Hiyoshi Yamada

Yasuaki Kasai

Shozo Abeyama

Chiaki Asada

Seishi Yajima

Shinichiro Yahagi

Tetsuo Kato

Hideo Kayano

Masashi Mizuno

Hiroyasu Nagasaka

Teruo Watanabe

Yutaka Yoshida

Katuhiro Kozima

Hisashi Kajima

Toshiya Kinami

Shigeki Sawa

A rotor comprises a rotor body and a ring-shaped rare earth metal-iron type magnet arranged therearound, in which a low thermal-expansion material is inserted between the rotor body and the magnet.

Rotor provided with a ring-shaped magnet

A method for producing an anisotropic rare earth magnet is improved by applying compressing stress on a free surface of an compacted material at the time of extruding the compacted material in order to prevent forming cracks, and improved by using a double action punch provided with a core punch and a sleeve punch so as to mold a compacted material and extrude the compacted material into the anisotropic magnet material in a single heat process continuously.

Method and apparatus for producing anisotropic rare earth magnet

Method for manufacturing a tapered rod for a coil spring from a metallic material of mainly steel in a linear state, by imparting heating to the same with a predetermined temperature gradient pattern in the axial direction thereof while or before pulling by tensile force the metallic material chucked at two axially distant points in either direction in a gradually decreasing or stepwise decreasing speed, until a desired tapered portion is formed. An apparatus preferably employed for this method comprises a pulling mechanism for chucking and pulling the material, an electric current supplying mechanism for supplying predetermined amount of current to the material between the two chucked points, a plurality of cooling units arranged axially along the material for positionwise cooling the material so as to make the temperature gradient thereon, a temperature detecting device for detecting the surface temperature of the material for feeding back the detected data to the current supplying mechanism, and a heating temperature controlling device for controlling the amount of the current flowed there.

Method for manufacturing tapered rods

Sulfur-containing free-cutting steel may have an improved machinability and fewer defects by adding certain amounts of Te, Pb and Bi to prevent elongation of sulfide inclusion particles, and by lowering Al-content to decrease Al.sub.2 O.sub.3 of oxide inclusions or by lowering O-content to decrease large Al.sub.2 O.sub.3 inclusion particles. The free-cutting steel may be produced by continuous casting.

Free cutting steel

Method of thermal plastic working of metal materials whereby a material is heated or cooled with measurements being made of variations in the metallographical condition of the material which may occur as the temperature of the material is varied due to the foregoing treatment. If the measurement shows that the material has effected a sudden change in its metallographical condition, the temperature having caused such a sudden change or higher temperature may be used to perform a desired plastic working of the material in its most plastic-workable condition.

Method of plastic working of metal materials

A steel for cold forging containing C up to 0.6%, Si up to 0.5%, Mn up to 2.0%, S 0.003 to 0.04% and Te up to 0.03%, wherein ratio %Te/%S being at least 0.04, and further, Al up to 0.04%, N up to 0.02% and O up to 0.0030%, and the balance being substantially Fe exhibits both good formability in cold forging and good machinability. The steel may further contain one or more of additional alloying elements selected from the group of Ni, Cr and Mo, the group of V, Nb, Ti, B and Zr, and the group of Pb, Se, Bi and Ca. The steel for cold forging having good machinability is made preferably by agitating molten steel containing adjusted amounts of the alloying elements other than Te, and, if used, members of the Pb group, by introducing non-oxidizing gas thereinto so as to float up and separate large sized particles of non-metallic inclusions, and subsequently adding predetermined amount of Te and other elements.

Steel for cold forging having good machinability and the method of

Molybdenum base composite materials having high tensile strength and oxidon resistance at high temperatures are produced by piling in parallel and embedding silicon carbide fibers containing 0.01-20% by weight of free carbon, which have been produced by the specific method already disclosed in U.S. patent application Ser. No. 677,960, in molybdenum base metallic powders and by compressing and sintering the assembly.

Molybdenum base composite materials reinforced with continuous silicon

Cobalt or cobalt alloy composite materials reinforced with continuous silicon carbide fibers, which have a high tensile strength, a low elongation, a high Young modulus and a high tensile strength at a high temperature, are produced by filling spaces in piles of the continuous silicon carbide fibers containing 0.01%-30% by weight of free carbon with melted or powdery metallic cobalt or cobalt alloy and integrating the said fibers with the said metal.

Growing community of inventors

Nagoya, Japan

Makoto Saito