| 摘要 |
PURPOSE:To cast continuously a billet having high quality without defects such as internal creck or the like at a high speed by specifying the respective surface temp. on the side of the billet where tensile stress is generated in the stage of straightening, on the side where compressive stress is generated and on short sides in the relation with the initial radius of curvature. CONSTITUTION:The billet temp. on the side where tensile stress is generated when a curved ingot having an initial radius R[m] of curvature is unbent so as to be straightened is designated as TL, the billet surface temp. on the side where compressive stress is similarly generated is designated as TF and the surface temp. on the short sides in the billet section is designated as TS in the straightening stage of the curved billet having an unsolidified phase by a continuous casting method at >=1.5m/min casting speed. The steel is cast continuously in the state satisfying the conditions -14.3R+1,043>=TL>=700, -14.3R+1,143>=TF>= (1+a) TL-b, TS>=900 where DELTAT=TF-TL, a=-0.0125R+0.205, b=-5.13R+ 81.25. |
