process to reduce the harmfulness of a steel's segregated veins, high mechanical strength steel and high wear resistance, process to fabricate a steel part and steel part

摘要

Process for Reducing the Harness of the Segregated Grapes of an Steel, High Mechanical Resistance Steel and High Wear Resistance, Process for Manufacturing a Steel Part and Steel Part The present invention relates to a process for reducing the segregated veins of a steel. high mechanical strength and wear-resistant steel the composition of which comprises by weight: 0,30% 243 C 243 1,42%; 0.05% 243 Si 243 1.5%; Mn 243 1.95%; Ni 243 2.9%; 1.1% 243 Cr 243 7.9%; 0.61% 243 Mo 243 44%; optionally V 1.45% Nb 1.45%, Ta 1.45%, and V + Nb / 2 + Ta / 4 1.45%; less than 0,1% boron, 0,19% (S + Se / 2 + Te / 4), 0,01% calcium, rare earth 0,5%, 1% aluminum and 1% copper; the rest being iron and impurities that result from elaboration. The composition further satisfies at: 800 243 D 243 1,150 with D = 540 (C) ¬ 0.20¬ + 245 (Mo + 3V + 1.5 Nb + 0.75 Ta) ¬ 0.30¬ + 125 Cr¬ 0.20¬ + 15.8 Mn + 7.4 Ni + 18 Si. In accordance with the procedure, all or part of the molybdenum is replaced by a double tungsten ratio such that W 0.21% and adjust Ti, Zr and C so that after adjustment Ti + Zr / 2 = 0.2 W, (Ti + Zr / 2) x C = 0.07, Ti + Zr / 2 = 1.49 % e D remain unchanged with a tolerance of 5%. The present invention also relates to the steel obtained and manufacturing process of a steel part.