PROCESS FOR PRODUCING HIGH STRENGTH STEEL

摘要

Process for producing a high strength steel, wherein the process comprises producing a vacuum-degassed steel melt, wherein the target oxygen content of the melt at the end of the ladle treatment is obtained by measuring the actual oxygen content of the melt and the oxygen level is adjusted by adding Al and/or Zr whereby the excess addition of Al should be avoided and the target oxygen content of the melt at the end of the ladle treatment is at most 100 ppm. Upon casting the steel a strip or slab is obtained of ultra-low carbon steel comprising at most 0.002 % of acid soluble Al and at most 0.004 % Si and a total oxygen content of at most 150 ppm.