混合粉を用いたマルエージング鋼の作製

抄録

The maraging steels are the excellent structural materials having both ultra-high strength and high toughness. To fabricate components of these steel, the conventional powder metallurgical process using a mixture of elemental powders including carbonyl iron powder was applied. The influences of ball-milling and sintering conditions on densification and alloying of the mixed powder compacts were investigated, and also the mechanical properties of the sintered and aged compacts were measured. The mixed powder compacts showed very high sinterability. When sintered at 1300°C, for 5h, the mixed powder compact reached to almost full density. In this compact, homogeneous alloying was confirmed by X-ray diffraction. The maximum tensile strength (1544 MPa) was obtained for the steel by the aging at 530°C for 2h. The elongation of the sintered maraging steels increased with the aging temperature.