李雪兆, 李双江, 董丽霞, 等. 70 t LD-LF-VD-CC流程生产耐候钢S355J2的工艺实践[J]. 特殊钢, 2016,37(1):37-39.
李雪兆, 李双江, 董丽霞, et al. Practice of Process for Production of Weathering Steel S355J2 by 70 t LD-LF-VD-CC Flowsheet[J]. Special Steel, 2016, 37(1): 37-39.
李雪兆, 李双江, 董丽霞, 等. 70 t LD-LF-VD-CC流程生产耐候钢S355J2的工艺实践[J]. 特殊钢, 2016,37(1):37-39.DOI:
李雪兆, 李双江, 董丽霞, et al. Practice of Process for Production of Weathering Steel S355J2 by 70 t LD-LF-VD-CC Flowsheet[J]. Special Steel, 2016, 37(1): 37-39.DOI:
0.025~0.050Als)的冶炼流程为70 t LD-LF-VD-280 mm×320 mm坯CC工艺。通过控制LD终点[C
]
≤0.07%
终点[P
]
≤0.014%
转炉下渣量≤2 kg/t和LF精炼渣碱度R≥3.0
(Al
2
O
3
)=20%等工艺措施
铸坯的T[O
]
为22×10
-6
夹杂物平均直径为4.6μm
5μm以下夹杂物比例在97.5%以上。连铸过程采用R=1.02
6.9%(B
2
O
3
+Li
2
O)
5.4%MgO和7.6% Al
2
O
3
的含氟保护渣
连铸坯表面震痕较浅
表面无清理率达到95.17%。连铸坯缩孔、疏松≤1.0级
角部、边部和中心裂纹为0级
满足连铸坯质量的控制要求。
Abstract
The metallurgical flowsheet of weathering steel S355J2 (/% : 0. 07 ~0. 12C
0.25 ~0. 40Si
1.0 ~1. 3Mn
≤0. 015P
≤0. 008S
0. 25 ~0. 40Cu
0. 35 ~0. 50Cr
0. 10 〜0. 25Ni
0. 025 ~ 0. 040Nb
0. 025 ~0. 050Als) is 70 t LD-LF-VD-280 mm x 320 mm bloom CC process. With the process measures including controlling LD end [C
]
≤0. 07%
end [P
]
≤0. 014%
converter tapping slag amount ≤2 kg/t
and refining slag basicity R ≥3.0 and (A1
2
O
3
)= 20%
the T[O
]
in casting bloom is 22 x 10
-6
average diameter of inclusions is 4. 6 μm with ratio of less than 5 μm inclusions more than 97. 5%. By using the bearing fluorine mold powder with basicity = 1. 02
6. 9% ( B
2
O
3
+ Li
2
0)
5. 4% MgO and 7. 6% A1
2
O
3
the bloom oscillation mark is slight
and the ratio of bloom surface without cleaning is up to 95. 17% . The rating of shrinkage and porosity of bloom ≤l. 0
and the rating of crack at comer
edge and center of bloom is 0 to meet the control requirement of bloom quality.