Feng Weimin,Xue Jingheng,Xing Guocheng,et al.Development of Mold Flux for Continuous Casting of Cr13 Type Martensitic Stainless Steel Square Billet[J].Special Steel,2023,44(03):53-58.
The surface depressions and longitudinal cracks of 2Cr13, 3Cr13, and 4Cr13 casting billets produced through 4-machine and 4-strand continuous casting machines in a special steel plant were analyzed and studied, the surface depression and longitudinal cracks of Cr13 stainless steel billet were solved by processing measures. Pre-melting mold flux consisting of 28%-31% SiO
2
, 28%-31% CaO , 6%-9% Al
2
O
3
, 7%-10% Na
2
O and 3%-6% F were used, and comprehensive carbon preparation, especially the addition of carbon black was increased; the total carbon content was 15%-18%. The basicity of mold flux was controlled at about 1.0, the melting temperature was 1130-1150 ℃, and the viscosity at 1300 ℃ was 0.40-0.55 Pa·s. The turning temperature of the mold flux was 1140-1180 ℃, and the crystallization rate was about 48.8%. The superheat of 2Cr13 liquid steel in the tundish should be less than 30 ℃, and the superheat of 3Cr13 and 4Cr13 liquid steel should be less than 35 ℃. Automatic slagging is adopted in continuous casting process to control appropriate slag layer thickness and keep liquid level stable.
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