低酸素構造用鋼(ULO鋼)の特性について
1980 年 51 巻 1 号 p. 4-12
詳細
1980 年 51 巻 1 号 p. 4-12
Properties of ultra-low oxygen structural steels with oxygen content below 15ppm produced by combination of RH degassing and Ar gas shielded casting techniques were studied. The following results were obtained in comparison to steels produced by conventional process.
1. Drastic decrease is observed in occurence of macroscopic streak flaw. Smaller number of non-metallic inclusions leads to improved cleanliness.
2. Decreased scatter in chemical compositions enables more precise control of hardenability.
3. Fatigue endurance limit as well as rolling contact fatigue life is increased.
4. Cold forgeability is improved, hence lower probability of crack initiation.
5. No significant improvement in machinability is observed.
