Patents by Inventor Yoshiaki Shimoyama

Yoshiaki Shimoyama has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4851056
    Abstract: In a conventional process for producing a semi-processed non-oriented electrical steel sheet, the silicon or aluminum content of a hot-rolled steel strip is high, especially in the case of producing a high-grade electrical sheet which has a low watt loss. However, a high silicon or aluminum content disadvantageously results in a decrease in the magnetic flux density.A decrease in the watt loss and an increase in the magnetic flux density in semi-processed non-oriented electrical steel sheets as compared with conventional high-grade semi-processed non-oriented electrical steel sheets can be achieved by making the silicon content, which increases resistivity, low, i.e. from 0.1 to 1.0%, and the manganese content, which is effective for improving the texture, high i.e. from 0.75 to 1.5% and by subjecting the starting material, having a low silicon content, and a high manganese content to an appropriate production process for controlling texture.
    Type: Grant
    Filed: May 29, 1987
    Date of Patent: July 25, 1989
    Assignee: Nippon Steel Corporation
    Inventors: Kunisuke Miyoshi, Yoshiaki Shimoyama, Takeshi Kubota
  • Patent number: 4797167
    Abstract: Method for the production of a single oriented silicon steel sheet having excellent magnetic property which comprises providing a silicon steel slab containing 0.010.about.0.10% C, 2.5.about.4.5% Si, 0.02.about.0.15% Mn, and a total of 0.008.about.0.080% of one or two of S and Se, hot rolling the silicon steel slabing to sheet, and subjecting the hot rolled sheet to a two-step annealing procedure wherein the first half is at a temperature of 1000.degree..about.1200.degree. C. and the latter half at 750.degree..about.980.degree. C., and to at least two cold rolling steps.
    Type: Grant
    Filed: July 2, 1986
    Date of Patent: January 10, 1989
    Assignee: Nippon Steel Corporation
    Inventors: Hisanobu Nakayama, Shouzaburo Nakashima, Yoshiaki Shimoyama, Yasukazu Mori
  • Patent number: 4666534
    Abstract: In the production of non-oriented electrical steel sheets, it has been attempted to decrease the watt loss, e.g., by adding Sn to silicon steels, but in such a case the relationship between the watt loss and the magnetic flux density falls within the curves 1 and 1' in FIG. 1. The addition of boron is therefore unsatisfactory for meeting the recent demand for improving the magnetic properties of a non-oriented electrical steel sheet over those indicated by the curve 3.In the present invention, the combined addition of Sn and B and/or sol. Al results in the development of (110) and (100) textures, which are desirable for the magnetic properties.A non-oriented electrical steel sheet according to the present invention consists of:at most 0.015% carbon,0.3% to 2.0% silicon,0.02% to 0.20% tin,and optionally1.0% to 1.5% manganese,and(a) 0.005% to 0.10% acid-soluble aluminium,at most 0.007% nitrogen,at most 0.005% boron,the weight ratio of the boron content/nitrogen content being from 0.5 to 1.
    Type: Grant
    Filed: September 4, 1985
    Date of Patent: May 19, 1987
    Assignee: Nippon Steel Corporation
    Inventors: Kunisuke Miyoshi, Yoshiaki Shimoyama, Takeshi Kubota
  • Patent number: 4661174
    Abstract: In the production of non-oriented electrical steel sheets, it has been attempted to decrease the watt loss, e.g., by adding Sn to silicon steels, but in such a case the relationship between the watt loss and the magnetic flux density falls within the curves 1 and 1' in FIG. 1. The addition of boron is therefore unsatisfactory for meeting the recent demand for improving the magnetic properties of a non-oriented electrical steel sheet over those indicated by the curve 3.In the present invention, the combined addition of Sn and B and/or sol. Al results in the development of (110) and (100) textures, which are desirable for the magnetic properties.A non-oriented electrical steel sheet according to the present invention consists of:at most 0.015% carbon,0.3% to 2.0% silicon,0.02% to 0.20% tin,and optionally1.0% to 1.5% manganese,and(a) 0.005% to 0.10% acid-soluble aluminium,at most 0.007% nitrogen,at most 0.005% boron,the weight ratio of the boron content/nitrogen content being from 0.5 to 1.
    Type: Grant
    Filed: May 25, 1984
    Date of Patent: April 28, 1987
    Assignee: Nippon Steel Corporation
    Inventors: Kunisuke Miyoshi, Yoshiaki Shimoyama, Takeshi Kubota
  • Patent number: 4560423
    Abstract: The present invention relates to a process for producing a non-oriented silicon steel sheet having a low watt loss and an improved magnetic flux density. Generally, increasing the content of silicon and aluminum in a steel reduces the watt loss of the final product but deteriorates the magnetic flux density. Also, increasing the finishing temperature of a steel sheet or to increase the size of the crystal grains of the final product reduces the watt loss of the final product but also decreases the magnetic flux density.In accordance with the present invention, a grade S7 or grade S8 non-oriented electromagnetic steel sheet exhibiting such excellent magnetic properties at a high magnetic field that the magnetic flux density B.sub.50 is 1.67 tesla or more, the watt loss W.sub.15/50 is 2.70 W/kg or less (0.50 mm thick), and the watt loss W.sub.15/50 is 2.20 W/kg or less (0.35 mm thick) is produced by subjecting a high aluminum electromagnetic steel containing not less than 2.5% silicon and not less than 1.
    Type: Grant
    Filed: March 15, 1983
    Date of Patent: December 24, 1985
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiaki Shimoyama, Kunisuke Miyoshi, Yoshitaka Hiromae
  • Patent number: 4555264
    Abstract: The present invention relates to a process for producing an electrical steel sheet. In order to prevent aging deterioration of the electrical steel sheet, the carbon content of the steel for the sheet should be reduced to an extremely low level, e.g., 0.0030% or less. However, when molten steel was subjected to vacuum-degassing and continuous-casting procedures to prepare steel for a electrical steel sheet in a prior art, although a desired carbon content of the molten steel was ensured at the degassing stage, the carbon content of the steel sometimes exceeded the desired level at the slab range. In the present invention, the prior art problem is solved by carrying out the degassing procedure under conditions in which the ultimate degree of vacuum in the degassing vessel is 1.0 mmHg or less, the rate of inert gas blown per gas-blowing orifice is from 30 to 150 Nl/min, and the final carbon content of the molten steel is 0.
    Type: Grant
    Filed: August 25, 1982
    Date of Patent: November 26, 1985
    Assignee: Nippon Steel Corporation
    Inventors: Takeaki Takeshita, Katuyuki Oba, Yoshiaki Shimoyama, Takashi Masuda
  • Patent number: 4439251
    Abstract: A non-oriented magnetic material consisting essentially of .ltoreq.0.065% C, .ltoreq.0.10% Al, 0.31 to 3.15% Si, .ltoreq.0.020% O, .ltoreq.0.01% N and B present in such amounts that the ratio of B/N is in the range of 0.5 to 2.50. The non-oriented magnetic material of this invention is produced by hot rolling a material of the above composition, subjecting the hot-rolled sheet to at least one cold-rolling step with intermediate annealing followed by a continuous annealing step and optionally a reannealing step to produce a non-oriented magnetic material.
    Type: Grant
    Filed: July 27, 1981
    Date of Patent: March 27, 1984
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiaki Shimoyama, Ichiro Tachino, Shigenobu Koga
  • Patent number: 4338143
    Abstract: A non-oriented silicon steel sheet with a low watt loss value as well as uniform magnetic properties which contains 1.5-3.5% Si, an exceedingly low C content, and a low soluble Al content, and has a ratio of B to N in the range of 0.4 to 2.0, and further contains at least one rare earth element.
    Type: Grant
    Filed: March 27, 1981
    Date of Patent: July 6, 1982
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiaki Shimoyama, Shigenobu Koga, Katsuyki Ohba
  • Patent number: 4280837
    Abstract: In the continuous casting of slabs for use in manufacturing grain-oriented electrical steel sheet and strip, the slag covering the molten steel for casting the slabs is adjusted in its composition to maintain the ratio of Al.sub.2 O.sub.3 to SiO.sub.2 at not less than 0.25, whereby the slabs continuously cast from the molten steel are made free from variation in Al or Al and S content in the direction of casting.
    Type: Grant
    Filed: October 31, 1979
    Date of Patent: July 28, 1981
    Assignee: Nippon Steel Corporation
    Inventors: Morio Shiozaki, Mitsuaki Kawashima, Yoshiaki Shimoyama, Nobuoki Ishihara
  • Patent number: 4066479
    Abstract: Process for producing non-directional electric steel sheets free from ridging, comprising preparing slabs by continuous casting from molten steel comprising not more than 0.04% C, 1.5 to 4.0% Si, not more than 1.0% Al, the balance being Fe and unavoidable impurities, hot rolling, cold rolling and annealing the slabs, characterized in that the slab is subjected to breaking-down with a reduction rate between 10 to 70% in the sheet thickness direction at a temperature between 1000.degree. and 1300.degree. C, and subsequently the required treatments are done.
    Type: Grant
    Filed: July 6, 1973
    Date of Patent: January 3, 1978
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiaki Shimoyama, Kunisuke Miyoshi
  • Patent number: 3935038
    Abstract: A method for manufacturing non-oriented electrical steel sheet and strip having no ridging characterized in that, non-oriented electrical steel sheet and strip is manufactured by casting molten silicon steel into a slab, hot-rolling, cold-rolling and annealing, said molten silicon steel, being controlled so as to give a composition, at the time of hot-rolling, comprising C <0.06%, Si 1.5 - 4.0% and Al < 1.0%, with the relation Si + Al > 2.0% and also C .gtoreq. 1/100 [(Si + Al) - 0.75]% with the remainder being iron and unavoidable impurities.
    Type: Grant
    Filed: December 3, 1974
    Date of Patent: January 27, 1976
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiaki Shimoyama, Kunisuke Miyoshi, Hiroyuki Kimura