摘要:
The present invention provides a maraging steel containing: 0.10≦C≦0.30 mass %, 6.0≦Ni≦9.4 mass %, 11.0≦Co≦20.0 mass %, 1.0≦Mo≦6.0 mass %, 2.0≦Cr≦6.0 mass %, 0.5≦Al≦1.3 mass %, and Ti≦0.1 mass %, with the balance being Fe and unavoidable impurities, and satisfying 1.00≦A≦1.08, in which A is 0.95+0.35×[C]−0.0092×[Ni]+0.011×[Co]−0.02×[Cr]−0.001×[Mo], where [C] indicates a content (mass %) of C, [Ni] indicates a content (mass %) of Ni, [Co] indicates a content (mass %) of Co, [Cr] indicates a content (mass %) of Cr, and [Mo] indicates a content (mass %) of Mo, respectively. The maraging steel has a tensile strength of 2,300 MPa or more and is also excellent in the toughness/ductility and fatigue characteristics.
摘要:
Ups and downs having a cycle of not more than 5 &mgr;m and an amplitude of not less than 200 nm are formed in a part of not less than 70% per unit length of a prior-austenite grain boundary which is observed in a linear form when seen from a vertical plane by a series of steps of subjecting a steel in a state of austenite to a deformation in not less than 30% of a total area reduction rate at a temperature region which is lower than recrystallization temperature of austenite, and subsequently cooling a deformed steel without causing neither recrystallization nor phase transformation of a diffusion type.
摘要:
The present invention provides a maraging steel containing: 0.10≦C≦0.30 mass %, 6.0≦Ni≦9.4 mass %, 11.0≦Co≦20.0 mass %, 1.0≦Mo≦6.0 mass %, 2.0≦Cr≦6.0 mass %, 0.5≦Al≦1.3 mass %, and Ti≦0.1 mass %, with the balance being Fe and unavoidable impurities, and satisfying 1.00≦A≦1.08, in which A is 0.95+0.35×[C]−0.0092×[Ni]+0.011×[Co]−0.02×[Cr]−0.001×[Mo], where [C] indicates a content (mass %) of C, [Ni] indicates a content (mass %) of Ni, [Co] indicates a content (mass %) of Co, [Cr] indicates a content (mass%) of Cr, and [Mo] indicates a content (mass%) of Mo, respectively, The maraging steel has a tensile strength of 2,300 MPa or more and is also excellent in the toughness/ductility and fatigue characteristics.