李永超, 李宝秀, 郭明仪, et al. Influence of Aluminum Content and Surface Quenching on Surface Cracking of Hot-Charging Casting Bloom of Cold-Heading Steel SWRCH22A[J]. Special Steel, 2016, 37(1): 40-42.
李永超, 李宝秀, 郭明仪, et al. Influence of Aluminum Content and Surface Quenching on Surface Cracking of Hot-Charging Casting Bloom of Cold-Heading Steel SWRCH22A[J]. Special Steel, 2016, 37(1): 40-42.DOI:
Steelmaking process flowsheet for steel SWRCH22A is 80 t top and bottom combined blown converter-LF- 280 mm x 325 mm bloom casting. It is obtained by analysis that main cause for surface crack of hot-charging casting bloom of steel SWRCH22A is AIN precipitated at grain boundary during cooling to weaken the boundary and lead to crack under action of thermal stress and structure stress. With decreasing the Al content in bloom from 0. 053% to 0. 042%
decreasing nitrogen content from 0.005 5% to 0. 004 1%
as well as in-line surface quenching bloom before heating
the AIN precipitation is effectively inhibited
and the qualified ratio of hot-charged casting bloom increases from 77. 9% to 100%.