EAF→LF→VD工艺生产2100MPa级低合金超高强度钢试验

EAF→LF→VD technological test of 2100 MPa grade ultra-high strength low alloy steel

为提高2 000 MPa级以上的超高强度钢生产效率,降低工序成本,形成批量产能,进行了EAF→LF→VD取代VIM-ESR工艺试验。试验结果表明:钢中氧、氮、氢质量分数总和小于50×10-6,A、B、C类夹杂物评级为0级,D类夹杂物评级不大于1.0级。成品钢板经淬火和低温回火后其强度大于2 100MPa,伸长率大于7%,与VIM-ESR工艺相当。新工艺的成本降低44%以上,生产效率得到提高,适合低合金超高强度钢的规模化生产。

EAF→LF→VD technological test was conducted to replace VIM-ESR in order to increase the production efficiency and to reduce process cost of over 2 000 MPa grade ultra-high strength low alloy steel for mass production capacity. The test result shows that the total mass fraction of O, N and H in steel is smaller than 50 × 10^-6 ;the non-metallic inclusion of A, B and C class is evaluated as 0 grade and class D inclusion is less than 1.0 grade. The tensile strength of finished steel plate is more than 2 100 MPa after quenching and low tempering and its elongation is greater than 7 %, which is equivalent to the result of using VIM-ESR technology. By using the new technology, the cost is reduced by over 44 % and the production efficiency is increased. The new technology is suitable for large-scale production of ultra-high strength low alloy steel.