Abstract: Edge crack of 5 mm strip coil of S31803 duplex stainless steel ( % ：0. 019C,22. 50Cr,5. 40Ni ,3. 15Mo, 0. 18N) rolled from 200 mm slab is often occurred. It is available to prevent the formation of edge crack of 5 mm hot continuous-rolled strip coil by controlling S content in steel ≤0. 005% and adding RE-Si-Fe alloy to modify sulfide, decreasing oxygen content in steel from 53 x 10 ^-6 to 26 x 10 ^-6, increasing equiaxed zone ratio in cast slab, and-controlling slab heating temperature at 1 150 - 1 250℃.

Key words: Material Index Duplex Stainless Steel, Hot Continuous-Rolled Strip Coil, Edge Crack, Process Improvement

摘要： S31803双相不锈钢(%:0.019C、22.50Cr、5.40Ni、3.15Mo、0.18N)200 mm连铸坯热轧成5 mm卷板易产生边裂。通过控制钢中S含量≤0.005%,加RE-Si-Fe合金变质硫化物,将钢中氧含量由53×100^-6降至26×10^-6,提高铸坯等轴晶比例,控制铸坯加热温度1150～1250℃,有效地防止5 mm热连轧卷板边裂的产生。

关键词: 双相不锈钢, 热连轧卷板, 边裂, 工艺改进