Containing At Least 1.5 Percent Carbon Patents (Class 148/543)
  • Patent number: 5346561
    Abstract: The spheroidal graphite cast iron member having a surface layer portion mostly composed of a ferrite phase and having a thickness of at least 1 mm, and an inner portion composed of a pearlite phase and a ferrite phase, the surface layer portion having a ferritization ratio of 70% or more which is larger than that of the inner portion by at least about 15% is produced by (a) pouring a spheroidal graphite cast melt into a casting mold; (b) removing the casting mold by shake-out after the completion of solidification of the melt, while substantially the entire portion of the resulting cast iron product is still at a temperature of its A.sub.1 transformation point or higher; (c) when the temperature difference between the surface layer portion and the inner portion has become 40.degree.-60.degree. C., introducing the cast iron product into a uniform-temperature furnace kept at 750.degree.-900.degree. C.
    Type: Grant
    Filed: February 25, 1993
    Date of Patent: September 13, 1994
    Assignee: Hitachi Metals, Ltd.
    Inventors: Fumio Obata, Hisashi Yasuda, Hideaki Nagayoshi, Kiyoshi Suehara, Kouhei Imanishi, Toshiki Yoshida
  • Patent number: 5288342
    Abstract: A metallic solid comprising an metal-carbon matrix of an allotropic metal and metallofullerites of the allotropic metal is disclosed, along with an associated method of forming the solid by interrupting and temporarily holding a metal-carbon melt at the point through the cooling curve at which the solidifying metal passes through the allotropic transformation stage for the metal defined by the overall proportion of allotropic metal and carbon in the melt.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: February 22, 1994
    Inventor: Robert C. Job
  • Patent number: 5225007
    Abstract: The wear-resistant compound roll is constituted by a shell portion made of an iron-base alloy having the composition consisting essentially of 1.0-3.5 weight % of C, 3.0 weight % or less of Si, 1.5 weight % or less of Mn, 2-10 weight % of Cr, 9 weight % or less of Mo, 20 weight % or less of W, 2-15 weight % of V, 0.08 weight % or less of P, 0.06 weight % or less of S, 300 ppm or less of B, the balance being substantially Fe and inevitable impurities, and a shaft portion made of steel. The iron-base alloy of the shell portion has a structure containing by an area ratio 5-30 % of granular carbides and 5 % or less of non-granular carbides, an alloy matrix of the shell portion having a Vickers hardness (Hv) of 550 or more. This compound roll has excellent wear resistance and resistance to surface roughening.
    Type: Grant
    Filed: March 24, 1992
    Date of Patent: July 6, 1993
    Assignee: Hitachi Metals Ltd.
    Inventors: Toshiyuki Hattori, Masahiko Ooshima, Noriyoshi Fuchigami
  • Patent number: 5185044
    Abstract: A method of making a steel article having a "Damascus" surface pattern wherein a steel melt comprising about 1.0 to about 2.0 weight % carbon is solidified to form an ingot, the ingot is heated between about 1100.degree. to about 1299.degree. C. for a time at temperature of about 5 to about 12 hours, a malleable envelope is formed about the ingot separately or concurrently with the heat treatment, and the enveloped ingot is shaped (e.g., forged) initially at an ingot temperature above the A.sub.r-gr temperature but below the liquidus temperature and then at an ingot temperature below the A.sub.cm temperature. The envelope is then removed from the shaped ingot.
    Type: Grant
    Filed: January 29, 1992
    Date of Patent: February 9, 1993
    Inventors: John D. Verhoeven, Alfred H. Pendray
  • Patent number: 5122197
    Abstract: A cast-iron product has a composition of 4.3-4.9 wt. % Carbon Equivalent (CE), 0.25-0.5 wt. % Chromium (Cr), 0.05-0.12 wt. % Tin (Sn), 0.4-1.2 wt. % Manganese (Mn), 0-0.1 wt. % Phosphorus (P), and 0-0.15 wt. % Sulfur (S), with the balance being Iron (Fe). A brake assembly comprises a sliding element made of such a cast iron, and the sliding element is adapted to slideably contact with a friction element or elements made of non-asbestos material and constitute the assembly. Further, a method of producing a cast iron product comprises the steps of casting a cast iron having a composition of 4.3-4.9 wt. % Carbon Equivalent (CE), 0.25-0.5 wt. % Chromium (Cr), 0.05-0.12 wt. % Tin (Sn), 0.4-1.2 wt. % Manganese (Mn), 0-0.1 wt. % Phosphorus (P), and 0-0.15 wt. % Sulfur (S), with the balance being Iron (Fe), releasing a mold at a temperature not less than A.sub.1 allotropic transformation temperature, and cooling the cast iron at a relatively high cooling rate.
    Type: Grant
    Filed: August 28, 1990
    Date of Patent: June 16, 1992
    Assignee: Mazda Motor Corporation
    Inventors: Hiroshi Asai, Ichiro Kitayama, Kouji Mineshita, Ken Okazaki, Akira Ohtsuka, Yuichi Nishiyama, Yasuo Uosaki