公开(公告)号：CA2441839A1

公开(公告)日：2002-10-10

申请号：CA2441839

申请日：2002-04-02

Applicant: NUCOR CORP

Inventor： GROSS CLAY A ,  MAHAPATRA RAMA BALLAV ,  WIGMAN STEVEN LEONARD ,  BLEJDE WALTER

IPC: B22D1/00 ,  B22D11/116 ,  B22D11/117 ,  C21C5/34 ,  C21C7/00 ,  C21C7/06 ,  C21C7/064 ,  C21C7/072 ,  C21C7/076

Abstract: A steel charge and slag forming material is heated in a ladle to form molten steel covered by a slag containing silicon, manganese and calcium oxides. Th e steel is stirred by injection of an inert gas such as argon or nitrogen to cause silicon/manganese deoxidation and desulphurization to produce a silicon/manganese killed molten steel. Stirring of the molten steel by the inert gas injection while in contact with slag high in calcium oxide generat es low free oxygen levels in the steel and desulphurization to sulphur levels below 0.009%. The slag may subsequently be thickened by lime addition to prevent reversion of sulphur back into the steel and oxygen may be injected into the steel to increase its free oxygen content to produce a steel that i s readily castable in a twin roll caster.

公开(公告)号：CA2420492A1

公开(公告)日：2002-04-04

申请号：CA2420492

申请日：2001-09-28

Applicant: NUCOR CORP

Inventor： MUKUNTHAN KANNAPPAR ,  BLEJDE WALTER ,  STREZOV LAZAR ,  MAHAPATRA RAMA

IPC: B21B1/00 ,  B21B1/46 ,  B22D11/00 ,  B22D11/06 ,  B22D11/12 ,  B22D11/124 ,  C21D1/00 ,  C21D1/18 ,  C21D8/02 ,  C21D9/573 ,  C22C38/00 ,  C22C38/06

Abstract: Steel strips and methods for producing steel strips are provided. In an illustrated embodiment, a method includes continuously casting molten low carbon steel into a strip of no more than 5 mm thickness having austenite grains that are coarse grains of 100-300 micron width; and providing desired yield strength in the cast strip by cooling the strip to transform the austenite grains to ferrite in a temperature range between 850 ~C and 400 ~C at a selected cooling rate of at least 0.01 ~C/sec to produce a microstructu re that provides a strip having a yield strength of at least 200 MPa. The low carbon steel produced desired microstructure.

公开(公告)号：BRPI0212499B1

公开(公告)日：2015-12-08

申请号：BR0212499

申请日：2002-09-13

Applicant: NUCOR CORP

Inventor： MAHAPATRA RAMA BALLAV ,  BLEJDE WALTER ,  STREZOV LAZAR

IPC: B22D11/06 ,  B22D1/00 ,  B22D11/00 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06

Abstract: "processo para produzir tira de aço por fundição contínua e tira de aço fina produzida por fundição de cilindros gêmeos". expõe-se a fundição de tira de aço fina em cilindros gêmeos. aço fundido é introduzido entre um par de cilindros de fundição refrigerados para formar uma poça de fundição a partir da qual aço é solidificado nos cilindros para produzir uma tira solidificada. o aço fundido é dotado de um teor de oxigênio total na faixa de 100ppm a 250ppm e contém inclusões de óxido de metal que compreendem qualquer um ou mais de mno, sio~ 2~ e al~ 2~o~ 3~ distribuídos por todo o aço sob uma densidade de inclusões na faixa de 2 g/cm^ 3^ a 4 g/ cm^ 3^. tipicamente, as inclusões variam de dimensão entre 2 e 12 micrômetros. a tira fundida é dotada de uma espessura menor do que 5 mm e contém inclusões de óxido de metal solidificadas distribuídas de forma tal que as regiões da tira contêm inclusões solidificadas para uma densidade de área unitária de pelo menos 120 inclusões/mm^ 2^.

公开(公告)号：PL1989009T3

公开(公告)日：2015-10-30

申请号：PL07701554

申请日：2007-02-27

Applicant: NUCOR CORP

Inventor： BLEJDE WALTER ,  ONDROVIC JAY JON

IPC: B21B1/26 ,  B21B1/46 ,  B21B27/10 ,  B21B37/00 ,  B21B45/02

公开(公告)号：AT509716T

公开(公告)日：2011-06-15

申请号：AT02766948

申请日：2002-09-13

Applicant: NUCOR CORP

Inventor： BLEJDE WALTER ,  MAHAPATRA RAMA BALLAV ,  STREZOV LAZAR

IPC: B22D11/06 ,  B22D1/00 ,  B22D11/00 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06

Abstract: A method of producing strip comprising the steps of assembling a pair of casting rolls with a nip between them, introducing between the casting rolls to form a casting pool of molten carbon steel having a total oxygen content of at least 100 ppm and usually less than 250 ppm, counter rotating the casting rolls, solidifying the molten steel on the rolls to form metal shells with levels of oxide inclusions reflected by the total oxygen content of the molten steel, and forming thin steel strip through the nip between the casting rolls from the solidified shells. A unique steel strip may be obtained using the method having ductile properties.

公开(公告)号：CA2441839C

公开(公告)日：2010-03-09

申请号：CA2441839

申请日：2002-04-02

Applicant: NUCOR CORP

Inventor： BLEJDE WALTER ,  GROSS CLAY A ,  MAHAPATRA RAMA BALLAV ,  WIGMAN STEVEN LEONARD

IPC: B22D1/00 ,  C21C7/06 ,  B22D11/116 ,  B22D11/117 ,  C21C5/34 ,  C21C7/00 ,  C21C7/064 ,  C21C7/072 ,  C21C7/076

Abstract: A steel charge and slag forming material is heated in a ladle to form molten steel covered by a slag containing silicon, manganese and calcium oxides. Th e steel is stirred by injection of an inert gas such as argon or nitrogen to cause silicon/manganese deoxidation and desulphurization to produce a silicon/manganese killed molten steel. Stirring of the molten steel by the inert gas injection while in contact with slag high in calcium oxide generat es low free oxygen levels in the steel and desulphurization to sulphur levels below 0.009%. The slag may subsequently be thickened by lime addition to prevent reversion of sulphur back into the steel and oxygen may be injected into the steel to increase its free oxygen content to produce a steel that i s readily castable in a twin roll caster.

公开(公告)号：DK1386011T3

公开(公告)日：2009-03-23

申请号：DK02712642

申请日：2002-04-02

Applicant: NUCOR CORP

Inventor： GROSS CLAY A ,  MAHAPATRA RAMA BALLAV ,  WIGMAN STEVEN LEONARD ,  BLEJDE WALTER

IPC: B22D1/00 ,  C21C7/06 ,  B22D11/116 ,  B22D11/117 ,  C21C5/34 ,  C21C7/00 ,  C21C7/064 ,  C21C7/072 ,  C21C7/076

Abstract: A steel charge and slag forming material is heated in a ladle to form molten steel covered by a slag containing silicon, manganese and calcium oxides. The steel is stirred by injection of an inert gas such as argon or nitrogen to cause silicon/manganese deoxidisation and desulphurization to produce a silicon/manganese killed molten steel. Stirring of the molten steel by the inert gas injection while in contact with slag high in calcium oxide generates low free oxygen levels in the steel and desulphurization to sulphur levels below 0.009%. The slag may subsequently be thickened by lime addition to prevent reversion of sulphur back into the steel and oxygen may be injected into the steel to increase its free oxygen content to produce a steel that is readily castable in a twin roll caster.

公开(公告)号：MA30275B1

公开(公告)日：2009-03-02

申请号：MA31230

申请日：2008-09-10

Applicant: NUCOR CORP

Inventor： BLEJDE WALTER ,  ONDROVIC JAY JON

IPC: B21B1/26 ,  B21B1/46 ,  B21B27/10 ,  B21B37/00 ,  B21B45/02

Abstract: L'invention concerne un procédé de formation d'une bande mince de coulée présentant au moins une microstructure sélectionnée dans le groupe constitué par la ferrite polygonale, la ferrite aciculaire, la ferrite de Widmanstätten, la bainite et la martinsite, une rugosité de surface inférieure à 1,5 microns Ra et une épaisseur de calamine inférieure à environ 10 microns, lequel procédé consiste à appliquer un mélange d'eau et d'huile sur les cylindres de travail du laminoir à chaud, à faire passer la bande mince de coulée à une température inférieure à 1 100 °C à travers le laminoir à chaud dont les cylindres de travail sont enduits du mélange d'huile et d'eau et à protéger la bande mince de coulée des cylindres de coulée à travers le laminoir à chaud dans une atmosphère contenant moins de 5 % d'oxygène pour former la bande mince de coulée.

公开(公告)号：NZ541287A

公开(公告)日：2007-12-21

申请号：NZ54128704

申请日：2004-01-23

Applicant: NUCOR CORP

Inventor： MAHAPATRA RAMA BALLAV ,  BLEJDE WALTER

IPC: B22D11/06 ,  C22C38/06 ,  C22C38/04

Abstract: A method of producing cast steel strip having low surface roughness and low porosity by casting with molten steel having a total oxygen content of at least about 70 ppm and a free oxygen content between 20 and 60 ppm, and a temperature that allows a majority of any oxide inclusions to be in a liquidus state. The total oxygen content may be at least 100 ppm and the free oxygen content between 30 and 50 ppm. The steel strip produced by the method may have a per unit area density of at least 120 oxide inclusions per square millimetres to a depth of about 2 microns from the strip surface.

公开(公告)号：CO5560594A2

公开(公告)日：2005-09-30

申请号：CO04023653

申请日：2004-03-15

Applicant: NUCOR CORP

Inventor： BLEJDE WALTER ,  MAHAPATRA RAMA BALLAV ,  STREZOV LAZAR

IPC: B22D11/06 ,  B22D1/00 ,  B22D11/00 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06

Abstract: 1.- Un método para fabricar una tira de acero mediante fundición continua que comprende los pasos de:a. Ensamble de un par de rodillos de fundición enfriados que tienen una separación entre ellos y con cierres de confinación adyacentes de los extremos de la separación;b. Introducción de acero fundido entre el par de rodillos de fundición para formar una piscina de fundición entre los rodillos de fundición, el acero fundido es un acero bajo en carbono que tiene un contenido de carbono en el rango de 0.001 % a 0.01 % en peso, un contenido de manganeso en el rango de 0.01% a 2.0% en peso y un contenido de silicio en el rango de 0.01% a 10% en peso y un contenido de oxígeno total de al menos 100 ppm.c. Contra-rotación de los rodillos de fundición y solidificación del acero fundido para formar las capas metálicas sobre la superficie de los rodillos de fundición con niveles de inclusiones de oxido reflejados mediante el contenido de oxígeno total del acero fundido para promover la formación de una tira de acero delgada; y d. Formación de tira de acero delgada solidificada a través de la separación de los rodillos de fundición de dichas capas solidificadas.12.- Una tira de acero delgada producida mediante fundición en rodillos gemelos a un espesor de menos de 5 mm y formada de un acero solidificado que contiene inclusiones de óxido solidificadas distribuidas de forma que en las regiones de superficie de la tira a una profundidad de 2 micrones desde la superficie contiene dichas inclusiones a una densidad de unidad de área de al menos 120 inclusiones/mm2.