Patents by Inventor Chung San Lee

Chung San Lee 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: 6451128
    Abstract: A method for manufacturing a high magnetic flux density grain oriented electrical steel sheet is disclosed. A silicon steel slab is heated and hot-rolled, and the steel sheet is annealed and cold-rolled and decarburized. An annealing separator is spread on the steel sheet, and a final high temperature annealing is carried out. The silicon steel contains in weight % 0.02-0.045% of C, 2.90-3.30% of Si, 0.05-0.30% of Mn, 0.005-0.019% of Al, 0.003-0.008% of N, 0.006% or less of S (the above being main ingredients), 0.001-0.012% of B, and a balance of Fe and unavoidable impurities; or the above main ingredients plus 0.30-0.70% of Cu, 0.03-0.07% of Ni, 0.03-0.07% of Cr, and a balance of Fe and unavoidable impurities; or the above main ingredients plus 0.001-0.012% of B, 0.30-0.70% of Cu, 0.03-0.07% of Ni, 0.03-0.07% of Cr, and a balance of Fe and unavoidable impurities.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: September 17, 2002
    Assignee: Pohang Iron & Steel Co., Ltd.
    Inventors: Chung San Lee, Chan Hye Han, Jong Soo Woo, Gyu Seung Choi, Jae Kwan Kim, Byung Deuk Hong, Kyu Seok Han
  • Patent number: 5653821
    Abstract: A method for manufacturing an oriented electrical steel sheet includes the step of preparing a steel slab composed of in weight %: 0.035-0.050% of C, 2.9-3.3% of Si, less than 0.016% of P, 0.011-0.017% of soluble Al, 0.0080-0.012% of N, less than 0.007% of S, 0.06-0.18% of Ni+Cr, less than 0.32% of Mn with an Mn/S ratio of 20 or more, less than 0.6% of Cu with a Cu/Mn ratio of 1.5 or more, and balance of Fe and other inevitable impurities. The steel slab is heated at a temperature of 1250.degree.-1320.degree. C., and then hot rolled. The hot rolled slab is then cold rolled in two stages to a final sheet thickness, with a decarburization annealing being carried out at an intermediate thickness. The decarburized cold rolled sheet is coated with an annealing separator containing MgO as the main ingredient and then a finish annealing treatment is conducted, thereby obtaining a magnetically superior oriented electrical steel sheet.
    Type: Grant
    Filed: July 7, 1995
    Date of Patent: August 5, 1997
    Assignees: Pohang Iron & Steel Co., Ltd., Research Institute of Industrial Science & Technology
    Inventors: Gyu Seung Choi, Chung San Lee, Jong Soo Woo, Byung Deug Hong