Kobe Steel, Ltd.

Tetsushi Deura

Hitoshi Ishida

Daisuke Matsuwaka

Sei Kimura

Fumiaki Kudo

Koichi Sakamoto

Tomoko Sugimura

Tsuyoshi Mimura

Yosuke Shindo

Masaki Shimamoto

Masaki Kaizuka

Motohiro Nagao

Tomoya Shinozaki

Atsushi Tomioka

Shogo Fukaya

Akihiro Owaki

Takashi Abiko

Michio Nishihara

Eiji Otsuki

Shunsuke Hori

A method includes the production of a primary ingot, the production of a secondary ingot, and the removal of a flux layer. A CaO&#x2014;CaFflux in a content of 3-20 mass % and obtained by mixing 35-95 mass % of CaFwith CaO is added to a Ti&#x2014;Al alloy material including a total of at least 0.1 mass % of oxygen and at least 40 mass % of Al, and the resultant substance is melted by a melting method using a water-cooled copper container in an atmosphere having a pressure of 1.33 Pa or higher and held to produce the primary ingot. The primary ingot is continuously drawn downwards while being melted by a melting method using a bottomless water-cooled copper casting mould in an atmosphere having a pressure of 1.33 Pa or higher to produce the secondary ingot. The flux layer deposited on the surface of the secondary ingot is mechanically removed.

Method for producing Ti-Al alloy

Disclosed herein is a method for deoxidizing an Al&#x2014;Nb&#x2014;Ti alloy, which includes melting and holding an Al&#x2014;Nb&#x2014;Ti alloy containing from 50 to 75 mass % of Al, from 5 to 30 mass % of Nb, and 80 mass % or less in total of Al and Nb by a melting method using a water-cooled copper vessel in an atmosphere of 1.33 Pa to 2.67&#xd7;10Pa at a temperature of 1,900 K or more, thereby decreasing an oxygen content thereof. The Al&#x2014;Nb&#x2014;Ti alloy is prepared using an alloy material formed of an aluminum material, a niobium material and a titanium material and containing oxygen in a total amount of 0.5 mass % or more.

Method for deoxidizing Al&#x2014;Nb&#x2014;Ti alloy

A bearing steel material which contains 0.8-1.1 mass % C, 0.15-0.8 mass % Si, 0.1-1.0 mass % Mn, 1.3-1.8 mass % Cr, up to 0.05 mass % P (0 mass % is excluded), up to 0.015 mass % S (0 mass % excluded), 0.0002-0.005 mass % Al, 0.0002-0.0020 mass % Ca, 0.0005-0.010 mass % Ti, up to 0.0080 mass % N (0 mass % is excluded), and up to 0.0025 mass % O (0 mass % is excluded). The steel material contains oxide inclusions which have an average composition that comprises, in terms of mass %, 20-50% CaO, 20-50% AlO, 20-70% SiO, and 3-10% TiO.

Bearing steel material with excellent rolling fatigue property and bearing part

A steel wire rod is obtained, in which a gas flow rate during gas stirring in molten steel treatment is controlled to be 0.0005 Nm/min to 0.004 Nm/min per molten steel of 1 ton, thereby the rod satisfies a specified composition, and oxide base inclusions in any section including an axis line of the steel wire rod satisfy the following composition X, the inclusions having width of 2 &#x3bc;m or more perpendicular to a rolling direction, wherein the number of the oxide base inclusions of the following composition A is 1 to 20, and the number of the oxide base inclusions of the following composition B is less than 1: In the steel wire rod, drawability and fatigue properties are improved to the utmost.

Steel wire rod having excellent drawability and fatigue properties, and manufacturing method of the same

When the density (D) of the inclusions whose major axis exceeds 5 &#x3bc;m observed in the axis position of a section perpendicular to the axial direction of a forged product is made 70 nos/cmor below and the radius of the forged product is made R, the ratio of the density (D) of the inclusions whose major axis exceeds 5 &#x3bc;m observed in the R/3 position from the axis position toward the radial direction and the density Dsatisfies an inequality (1) below.0.5&#x2266;&#x2266;1.50&#x2003;&#x2003;(1)

Forged product and crankshaft manufactured from it

A forging steel has a dissolved Mg concentration within the range of 0.04-5 ppm by mass and a dissolved Al concentration within the range of 50-500 ppm.

Forging steel and its manufacturing method, and forged parts

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Kobe, Japan

Tetsushi Deura