Heat treatment process of vanadium-titanium-containing steel for axles of motor train unit

The invention relates to a heat treatment process of vanadium-titanium-containing steel for axles of a motor train unit. The heat treatment process comprises the following steps of firstly, normalizing: heating the vanadium-titanium-containing steel for the axles of the motor train unit to be 870 to 900DEG C, calculating the heating and heat preservation time of the temperature section according to 1.2 to 1.7min/mm, and performing air cooling; secondly, quenching (water quenching and oil quenching): heating the vanadium-titanium-containing steel for the axles of the motor train unit to be 850 to 880DEG C, calculating the heating and heat preservation time of the temperature section according to 1.5 to 2.0min/mm, and subsequently cooling; and thirdly, tempering: heating the vanadium-titanium-containing steel for the axles of the motor train unit to be 620 to 680DEG C, calculating the heating and heat preservation time of the temperature section according to 2 to 2.5min/mm, and subsequently performing air cooli