Mass fraction of elements not more than, %:
Carbon (C) 0,33-0,4; Silicon (Si) 0,90-1,20; Manganese (Mn) 0,20-0,50; Chromium (Cr) 4,80-5,50; Molybdenum (Mo) 1,10-1,50, Vanadium (V) 0,30-0,50; Nickel (Ni) up to 0,35; Copper (Cu) up to 0,3; Phosphorus (P) up to 0,03; Sulfur (S) up to 0,02.