李建民, 陈远清, 刘东风, et al. Optimization of Slab Concasting Process of 9 % Ni Steel for Liquefied Natural Gas Tank[J]. Special Steel, 2012, 33(5): 29-31.DOI:
The formation causes of occurred shell at meniscus in mold and network crack of slab surface in pilot con- casting production of 200 - 220 mm slab of 9% Ni steel (/% : ≤0. 10C
≤0. 35Si
0. 30 〜0. 80Mn
≤0. 005S
≤0. 008P
8. 5 ~ 10. ONi
≤0. 1OMo
≤0. 10A1) are analyzed
and the optimization on concasting process has been carried out. Results show that the calculated deviation of liquidus temperature of 9% Ni steel is the main cause led to the shell occurred at meniscus and based on experimental data by differential scanning calorimetry (DSC)
a new liquidus temperature calculation formula is established to get the liquidus temperature of tested 9% Ni steel
and as the overheat extent of liquid is 10 ~30 ℃
it is available to meet the requirement of slab concasting. With controlling [N
]
≤25 x 10
-6
[ Al
]
≤0. 03% and decreasing secondary cooli
ng water rate from 0. 6 L/kg to 0. 4 L/kg the concasting of 9% Ni steel is going on smoothly