Mass fraction of elements not more than, %: Carbon (C) 0,35-0,42; Silicon (Si) 0,2-0,45; Manganese (Mn) 0,3-0,6; Chromium (Cr) 1,35-1,65; Nickel (Ni) up to 0,3; Molybdenum (Mo) 0,15-0,25; Aluminium (Al) 0,7-1,1; Copper (Cu) up to 0,3; Phosphorus (P) up to 0,025; Sulphur (S) up to 0,025