Patent ID: 7445750

Claim:
Tool steel, the composition of which consisting of (the percentages being expressed in % by weight): 0.8 ≦ C ≦ 1.5 7.0 ≦ Cr ≦ 14 0.2 ≦ Mn ≦ 3 Ni ≦ 5 V ≦ 1 Nb ≦ 0.1 Si + Al ≦ 2 Cu ≦ 1 S ≦ 0.3 Ca ≦ 0.1 Se ≦ 0.1 Te ≦ 0.1 1.0 ≦ Mo + ½W ≦ 4 0.06 ≦ Ti + ½Zr ≦ 0.15 0.004 ≦ N ≦ 0.02 the balance of the composition consisting of iron and impurities resulting from the smelting, it being furthermore understood that: 2.5×10 −4 % 2 ≦(Ti+½Zr)×N.