摘要 |
A method by which high temperature properties of a ductile iron alloy, including creep and LCF properties, can be increased for pressure-containing components that are subject to creep and low cycle fatigue. The method comprises modifying the ductile iron alloy to contain 0.4 to 0.8 weight percent molybdenum. A casting of the modified ductile iron alloy is produced and then annealed at a temperature of at least 725° C. for not less than five hours to eliminate carbides and/or stabilize pearlite in the casting. The annealed casting of the modified ductile iron alloy exhibits improved creep resistance and low cycle fatigue properties in comparison to an identical casting of a ductile iron alloy that does not contain molybdenum.
|