Iron(fe) Or Iron Base Alloy Patents (Class 148/578)
  • Patent number: 5361968
    Abstract: A metallic press die having an edge portion or high pressure portion for processing a workpiece therewith is made by overlaying a welding material to that portion of a base material for the metallic press die which forms the edge portion or high pressure portion, and then machining an overlaid portion into a predetermined shape of the edge portion or high pressure portion. The welding material has a hardness after welding of HRC 45 or below. After the machining step, the overlaid portion is subjected to a subzero treatment to increase the hardness of the overlaid portion. The welding material contains, as a basic composition thereof, 0.5-1.5% by weight of carbon (C), 0.2 -2.0% by weight of silicon (Si), 0.3-6.0% by weight of manganese (Mn), 0.3-10.0% by weight of chromium (Cr), 0.3-10.0% by weight of cobalt (Co), and the remaining parts of iron (Fe) inclusive of unavoidable impurities, and wherein a starting temperature of martensitic transformation is 150 .degree. C. or below.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: November 8, 1994
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Keizou Tanaka, Noboru Nishikawa, Tsuyoshi Kawase, Masami Watanabe
  • Patent number: 5259200
    Abstract: A process for treating an article of metal containing material such as tool steel so as to improve the properties such as shockability, wearability, stability and hardness of the article. In one embodiment, the process comprises immersing the article at ambient temperature into liquid cryogenic material for a time period up to or equal to a set time period equal to the minimum cross-sectional dimension in inches times ten minutes. The article is then withdrawn from contact with the liquid cryogenic material and immediately subjected to a flow of air sufficient to raise the temperature of the article to ambient temperature in a period of time equal to or less than ten minutes plus ten minutes per minimum cross-sectional dimension in inches.
    Type: Grant
    Filed: August 30, 1991
    Date of Patent: November 9, 1993
    Assignee: Nu-Bit, Inc.
    Inventor: Dennis J. Kamody
  • Patent number: 5221372
    Abstract: A cryogenically-formed and tempered stainless steel is provided having improved fracture toughness and corrosion resistance at a given hardness level, such as, for example, of at least about Rc 60 for bearing applications. The steel consists essentially of, in weight %, about 21 to about 24% Co, about 11 to about 13% Cr, about 7 to about 9% Ni, about 0.1 to about 0.5% Mo, about 0.2 to about 0.3% V, about 0.28 to about 0.32% C, and the balance iron. The steel includes a cryogenically-formed martensitic microstructure tempered to include about 5 to about 10 volume % post-deformation retained austenite dispersed therein and M.sub.2 C-type carbides, where M is Cr, Mo, V, and/or Fe, dispersed in the microstructure.
    Type: Grant
    Filed: February 13, 1992
    Date of Patent: June 22, 1993
    Assignee: Northwestern University
    Inventor: Gregory B. Olson