Abstract: The process flowsheet of commercial-produced steel 4Cr5MoSiVl (/% : 0.38~0.40C, 0.88~0.92Si, 0.42~0.44Mn, 0.001〜0.003S, 0.007~0.014P, 5.00~5.55Cr, 1.37~1.40Mo, 0.98~1.00V, 0.015~0.025 Alt) is 65% hot metal +35% scrap-100 t EAF-LF-VD-Φ500mm bloom casting. With the process measures including controlling EAF end [C]0.06%~0.10% and end [P]0.006% , pre-deoxidizing by adding 1kg/t aluminium block during tapping, controlling LF refining slag basicity 2.5~3.0, soft argon stirring for ≥10 min after feeding calcium wire, VD ≤67 Pa, argon stirring with 100 x2 L/min for ≥15 min, supper heat extent of liquid in tundish 20~30℃ , casting mold electromagnetic stirring with 310 A and 1.5 Hz in casting, shielding casting and casting speed 0.34~0.35 m/min, the [O], [N] and [ N ] in 10 heats of steel 4Cr5MoSiVl is respectively 10 x 10^-6 ~ 12 x 10 ^-6, 72 x 10^-6 ~ 80 x 10^-6 and 1. 2 x 10^-6〜1.4 x 10^-6 , and each index of steel all meet the requirement of specification.

Key words: Die Steel 4Cr5MoSiV1, 100t EAF-LF-VD-Φ500mm bloom Casting, Production Practice

摘要： 生产的4Cr5MoSiV1钢（/%:0.3~80.40C，0.88~0.92Si，0.42~0.44Mn，0.001~0.003S，0.007~0.014P，5.00~5.55Cr，1.37~1.40Mo，0.98~1.00V，0.015~0.025Alt）的工艺流程为65%铁水+35%废钢-100t EAF-LF-VD-Φ500mm坯连铸-Φ120mm圆钢轧制。通过控制EAF终点[C]0.06%~0.10%,终点[P]0.006%,出钢加1kg/t铝块预脱氧,LF精炼渣碱度2.5~3.0,喂钙线后软吹≥10min,VD≤67Pa,100×2L/min氩气搅拌≥15min,中间包钢水过热20~30℃,连铸结晶器电磁搅拌（310A,1.5Hz）,保护浇铸,拉速0.34~0.35 m/min等工艺措施,10炉4Cr5MoSiVl钢中[O],[N]和[H]分别为10×10^-6~12×10^-6,72×10^-6~80×10^-6,1.2×10^-6~1.4×10^-6,各项指标均满足协议要求。

关键词: 模具钢4Cr5MoSiV1, 100t EAL-LF-VD-Φ500 mm坯连铸 , 生产实践