颜慧成, 范佳, 张凯, et al. Feature of Slab Solidification and Its Effect on Ultrasonic Inspection Defect of Medium Plate of Q355 Series and HSLA Steel and Process Improvement[J]. Special Steel, 2021, 42(6): 58-60.
颜慧成, 范佳, 张凯, et al. Feature of Slab Solidification and Its Effect on Ultrasonic Inspection Defect of Medium Plate of Q355 Series and HSLA Steel and Process Improvement[J]. Special Steel, 2021, 42(6): 58-60.DOI:
With sampling analysis on defects of Q355 series steel medium plate defect by ultrasonic inspection and heat-transferring simulation for slab solidification process
it is disclosed that the biconical liquid core appearing at slab solidifying front and C/Mn/H gathering in this zone are the cause of the medium plate two side ultrasonic inspection defect. Through process improvement and strict control
the RH vacuum degassing time ≥20 min
the whole process of continuous casting protecting
and hydrogen content of steel in mold ≤2 x 10
-6
and superheat of continuous casting less than 30 °C
the center carbon segregation of slab is better than 1.0 rating
combining slow cooling of slab and medium plate
the qualification rate of medium plate inspection is 99. 6% .