Spheroidal graphite cast iron and a method of manufacturing the same having excellent low-temperature impact resistance

摘要

PROBLEM TO BE SOLVED: To provide spheroidal graphite cast iron having such mechanical properties as ordinary tensile strength and extremely superior elongation and further to provide spheroidal graphite cast iron having such mechanical properties as excellent low temperature impact characteristics in addition to the above tensile strength and elongation.;SOLUTION: The spheroidal graphite cast iron has ≥650 MPa tensile strength and ≥10% elongation and also has ≥10 J/cm² impact value by the Charpy impact test (U-notch) at -40°C test temperature. The spheroidal graphite cast iron contains, by mass, 2.0 to 4.0% Ni, 0.05 to 0.20% Mn and 0.8 to 2.3% Si. The spheroidal graphite cast iron can be produced by being cooled at 0.1 to 1.0 °C/s cooling rate.;COPYRIGHT: (C)2004,JPO&NCIPI