Nisshin Steel Co., Ltd.

Nippon Steel Stainless Steel Corporation

Hiroshi Morikawa

Yasuhiro Suzuki

Yuuki Honda

Takashi Yamauchi

Shun Saito

Kazunari Morita

Yasuhiro Ehara

Hiroaki Cho

Noriaki Nukushina

Takahiro Fujii

Ryoji Hirota

Tomoharu Shigetomi

Yuki Honda

Kenjiro Ito

Katsunori Babazono

Teruhiko Suetsugu

A method for producing an austenitic stainless steel slab by continuous casting of an austenitic stainless steel, including applying electric power to the molten steel in a depth region providing a solidification shell thickness of from 5 to 10 mm at least at a center position in the long edge direction, so as to cause flows in directions inverse to each other in the long edge direction on both long edge sides, thereby performing electro-magnetic stirring (EMS) to control a continuous casting condition satisfying 10&#x3c;&#x394;T&#x3c;50&#xd7;F+10. Herein, &#x394;T represents a difference between an average molten steel temperature (&#xb0; C.) and a solidification starting temperature (&#xb0; C.) of the molten steel, and Frepresents a stirring intensity index shown by a function of a molten steel flow velocity in the long edge direction imparted by the electro-magnetic stirring and a casting velocity.

Method for producing austenite stainless steel slab

A continuous casting method includes discharging a molten steel from discharge ports of a submerged nozzle under conditions (A) and (B); and performing electro-magnetic stirrer (EMS) to cause flows in directions inverse to each other in the long edge direction on both long edge sides in the molten steel in a region having a depth providing a thickness of a solidification shell of from 5 to 10 mm at least at a center position in the long edge direction. (A) a discharge extended line from the discharge port of the submerged nozzle intersects a molten steel surface in the mold at a point P, and the position of the point P satisfies 0.15&#x2264;M/W&#x2264;0.45; and (B) a condition satisfying 0&#x2264;L&#x2212;0.17Vi&#x2264;350, wherein the unit for L is mm, and Vi represents a discharge velocity (mm/s) of the molten steel at the outlet opening.

Continuous casting method

In a continuous casting apparatusfor casting a stainless steel billet, a long nozzleextending into a tundishis provided at a ladlefor pouring a molten stainless steelin the ladleinto the tundish. Further, a nitrogen gasis supplied as a seal gas around the molten stainless steelin the tundish, and continuous casting of the stainless steel billetis performed, in which, while immersing the spoutof the long nozzleinto the molten stainless steelin the tundish, the molten stainless steelis poured through the long nozzleinto the tundishand the molten stainless steelin the tundishis poured into a casting mold

In a continuous casting method for casting aluminum-deoxidized molten stainless steelby using a continuous casting apparatusin which a long nozzleextending into a tundishis provided at a ladle, the molten stainless steelis poured into the tundishthrough the long nozzle, while the spoutof the long nozzleis being immersed in the molten stainless steelthat has been poured, and the molten stainless steelin the tundishis poured into a casting mold. A TD powderis sprayed so that the powder covers the surface of the molten stainless steelin the tundish, and nitrogen gas is supplied around the molten stainless steel. A calcium-containing material is added to the molten stainless steelin a state other than a state of retention in the tundish

In a continuous casting method for casting an aluminum-deoxidized molten stainless steelby using a continuous casting apparatusin which a long nozzleextending into a tundishis provided at a ladle, the molten stainless steelis poured through the long nozzleinto the tundish, while immersing a spoutinto the poured molten stainless steel, and the molten stainless steelin the tundishis poured into a casting mold. A TD powderis sprayed so that the powder covers the surface of the molten stainless steelin the tundish, a nitrogen gas is supplied around the molten stainless steel, and a calcium-containing material is added to the molten stainless steelin the tundish. The surface of the molten stainless steelafter casting is ground.

In a continuous casting devicefor casting a stainless steel billet, a long nozzleextending into a tundishis provided at a ladle. A molten stainless steelis poured through the long nozzleinto the tundish, and a spoutof the long nozzleis immersed into the poured molten stainless steel. During pouring, an argon gasis supplied around the molten stainless steelin the tundish. Further, continuous casting is performed, in which, while immersing the spoutof the long nozzleinto the molten stainless steelin the tundish, the molten stainless steelis poured from the ladleinto the tundishand poured from the tundishinto a casting mold. During casting, a nitrogen gasis supplied instead of the argon gasaround the molten stainless steelinside the tundish

An electric resistance material comprises an Fe&mdash;Cr&mdash;Ni alloy having composition of C up to 0.1%, Si up to 5%, Mn up to 6%, 9-32% Cr, 6-25% Ni, N up to 0.2%, 0-3% Mo, 0-4% Cu, 0-5% Al, 0-0.4% Ti, 0-0.4% Nb, 0-0.005% B and the balance being substantially Fe with the previsions that the value A defined by the formula (1) and the value B defined by the formula (2) are not less than 78 and not less than 14, respectively. The electric resistance material is high of resistivity with less temperature dependency, and a resistor made therefrom works well without noises during flow of electricity.

Electric resistance material

FE-CR soft magnetic material and a method of manufacturing thereof

A newly proposed steel consists of 8.0-35.0 wt. % Cr, 0.05-1.20 wt. % C, 0.05-3.0 wt. % at least one of Ti, Nb, Zr, V and W and the balance being essentially Fe and has the structure that a total amount of Ti, Nb, Zr, V and/or W carbide precipitates distributed in a steel matrix is adjusted to 0.l wt. % or more. The steel is bestowed with excellent abrasion-resistance by distribution of carbide precipitates. These carbides have nearly the same hardness as hard particles such as alumina and silicon carbides which causes abrasive abrasion. Due to such excellent abrasion-resistance, a weaving machine member, a sewing needle, an agricultural machine member such as a mowing tooth or a cutter blade made of the steel can be used over a long period.

Growing community of inventors

Yamaguchi, Japan

Hiroshi Morikawa