| 摘要 |
PURPOSE:To refine crystalline grains at a minimal draft, by heating a maraging steel to a temp. in a two-phase region of (alpha) and (gamma) for warm working and then by subjecting the above steel to solution heat treatment in a specific temp. region. CONSTITUTION:The maraging steel is heated to a temp. in the alpha+gamma two-phase region of 650-750 deg.C to undergo warm working so as to refine crystalline grains. Subsequently, solution heat treatment is applied at 820-850 deg.C to prevent embrittlement. By adopting this heat treating method, grains are refined and toughness is improved. This method is applicable to the improvement of toughness in a maraging steel to be used as material for aerospace equipment, extra- high pressure vessel, high-speed rotor, and the like. |
