Title:
SPHEROIDAL GRAPHITE CAST IRON, METHOD FOR MANUFACTURING SPHEROIDAL GRAPHITE CAST IRON, AND PARTS FOR VEHICLE WHEEL PERIPHERY
Document Type and Number:
WIPO Patent Application WO/2020/226037
Kind Code:
A1
Abstract:
Provided is a spheroidal graphite cast iron having high strength, high ductility, and high toughness, in particular, having a high tensile strength of at least 700 MPa, an elongation of at least 10%, and an absorption energy at room temperature of at least 10.0 J/cm2. The spheroidal graphite cast iron has a composition containing, in mass%, 3.0-4.0% of C, 2.0-2.4% of Si, 0.20-0.50% of Cu, 0.15-0.35% of Mn, 0.005-0.030% of S, and 0.03-0.06% of Mg, with Mn+Cu being below 0.45-0.75% and the remainder comprising Fe and inevitable impurities, and has a microstructure in which a ferrite layer surrounds spheroidal graphite crystallized in a pearlite matrix, wherein the microstructure has at least one point at which a portion of the pearlite extends from the matrix toward the spheroidal graphite to break through the ferrite layer.
Inventors:
TOBITA TOMOYUKI (JP)
Application Number:
PCT/JP2020/016462
Publication Date:
November 12, 2020
Filing Date:
April 14, 2020
Export Citation:
Assignee:
KK RIKEN (JP)
International Classes:
C22C37/04; C21D5/00
Domestic Patent References:
| WO2013100148A1 | 2013-07-04 |
Foreign References:
| JPS5921379B2 | 1984-05-19 | |||
| JPH0813079A | 1996-01-16 | |||
| JP2002317238A | 2002-10-31 | |||
| JP6079641B2 | 2017-02-15 |
Other References:
See also references of EP 3967785A4
Attorney, Agent or Firm:
SUGIMURA Kenji (JP)
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