STEEL FOR RAIL-BOUND VEHICLE WHEELS, PREFERABLY FOR RAILWAY VEHICLE WHEELS

摘要

Steel for rail-bound vehicle wheels, preferably for railway vehicle wheels, contains besides iron 0.58 to 0.65 % by weight carbon, 0.75 to 0.90 % by weight manganese, 0.25 to 0.40 % by weight silicon, maximum 0.008 % by weight phosphorus, maximum 0.005 % by weight sulphur, 0.10 to 0.20 % by weight nickel, 0.90 to 1.10 % by weight chromium, 0.070 to 0.150 % by weight molybdenum, 0.070 to 0.120 % by weight vanadium, minimum 0.014 % by weight aluminium. This steel is thermally treated in that it is heated up to a temperature from 800 to 815 °C during 4 to 5 hours, is kept at this temperature during 2 hours, is cooled down during 120 to 150 seconds in circulating water at a temperature from 50 to 70 °C, is tempered during 4 to 4.5 hours at a temperature from 630 to 650 °C, and is then finally cooled at a speed of 50 °C per hour.