HIGH-STRENGTH STEEL Russian patent published in 2013 - IPC C22C38/32 

FIELD: metallurgy.

SUBSTANCE: proposed composition contains the following substances, in wt %: carbon 0.07 - 0.18, manganese 0.40 - 1.50, silicon 0.17 - 0.80, molybdenum 0.10 - 0.14, vanadium - 0.15 -0.45, chromium 0.50 - 2.0, aluminium - 0.005- 0.012, nitrogen - 0.002 - 0.010, titanium 0.002 - 0.060, zirconium - 0.001-0.300,rare-earth metals - 0.01-0.07, calcium - 0.0003-0.0015, magnesium - 0.0003-0.010, boron - 0.001-0.007, sulfur - 0.005-0.015, iron making the rest. The following ratios are to be held: (Ti + Al) : N = 3.5 - 10.0 and (Zr + B + 0.5 rare earth metal) : Mo = 0.07 - 2.5.

EFFECT: higher strength, longer life.

2 tbl, 1 ex