| 摘要 |
PROBLEM TO BE SOLVED: To provide maraging steel having fatigue characteristics more excellent than those of the conventional one and to provide a method for producing it. SOLUTION: This maraging steel is the one having a chemical compsn. contg., by weight, <=0.01% C, 8 to 19% Ni, 8 to 20% Co, 2 to 9% Mo, 0.1 to 2% Ti, <=0.15% Al, <=0.003% N, <=0.0015% O, and the balance substantially Fe, and in which the componential segregation ratio between Ti and Mo is <=1.3. A cast piece of the steel having the above components is hot-forged at >=4 forging ratio and is next subjected to soaking treatment in which it is held in the temp. range of 1,100 to 1,280 deg.C for one or >= two times, and the total time of the soaking treatment is controlled to 10 to 100 hr to produce the maraging steel.
|
