The composition of an ultra high strength steel, the production process of an ultra high strength steel product and the product obtained

摘要

"Composition of an ultra high strength steel, the production process of an ultra high strength steel product and the product obtained.The present invention comprises a composition of ultra high strength steel intended to be used in a process comprising at least one step of the hot rolling mill.According to the invention,This composition has the following contents: C: between 1000ppm and 2500ppm; Mn: between 12000ppm and 25000ppm; Si: between 1500ppm and 3000ppm; P: between 100ppm and 600ppm; s: maximum 50ppm; N: not more than 100ppm; al: max.IMO 1000ppm; B: between 10ppm and 35ppm; tifator = Ti - 3Utm84-42n + 10: between 0ppm and 400ppm; Nb: between 200ppm and 800ppm; Cr: between 2500ppm and 7500ppm; Mo: between 1000ppm and 2500ppm; CA: between 0ppm and 50ppm; the remainder being substantially consisting of iron.Occasional impurities.