| 摘要 |
Fabrication of a strip or workpiece cut from a cold rolled maraging steel strip and hardened by heat treatment involves, prior to the heat treatment, subjecting the strip to cold plastic deformation with a rate of strain hardening greater than 30 % and to a recrystallization annealing to obtain a fine grain with an ASTM index greater than 8. The maraging steel composition comprises, by weight: (a) 12% <= Ni <= 24.5%; 2.5% <= Mo <= 12%; 4.17% <= Co <= 20%; Al <= 0.15%; Ti <= 0.1%; N <= 0.003%; Si <= 0.1%; Mn <= 0.1%; C <= 0.005%; S <= 0.001%; P <= 0.005%; H <= 0.0003%; and O <= 0.001%. The composition also satisfies the following relationships: (a) 20% <= Ni + Mo <= 27%; (b) 50 (c) Co asterisk Mo <= 200; (d) Ti asterisk N <= 2 asterisk 10<-4>. Independent claims are also included for; (a) the strip or workpiece obtained by this method; (b) a drive belt incorporating at least one of these strips; and (c) a support grill for an integrated circuit made up of a workpiece of this kind. |
