RAILROAD WHEEL HEAT TREATMENT METHOD Russian patent published in 2018 - IPC C21D9/34 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to the thermal treatment of railway wheels. Heat treatment of a railway wheel made of steel containing, by mass%: C 0.75–0.77; Mn 0.82–0.9; Si 0.3–0.4; Cr 0.18–0.25; Ni 0.15–0.25; V 0.02–0.04; Mo 0.04–0.06. Railway wheel is heated to the austenitizing temperature, a controlled cooling of the surface rim of the wheel is carried out for 420 with a liquid cooler or air mixture, while the cooling of the rim elements is carried out with water, adjusting its flow rate to individual elements of the rim during the cooling period, respectively: along the rolling circle from 0.005 to 0.006 l/(cm²⋅s) in the first period 120 s, from 0.006 to 0.007 l/(cm²⋅s) in the period 120 s, from 0.007 to 0.008 l/(cm²⋅s) in the period 60 s, from 0.008 to 0.009 l/(cm²⋅s) in the period 60 s, from 0.009 to 0.012 l/(cm²⋅s) in the period 60 s and the outer side surface of the wheel rim from 0.013 to 0.015 l/(cm²⋅s) in the first period 120 s, from 0.015 to 0.017 l/(cm²⋅s) in the period 60 s, from 0.020 to 0.022 l/(cm²⋅s) in the period 120 s, from 0.022 to 0.024 l/(cm²⋅s) in the period 120 s, and the inner side surface of the rim of the wheel is cooled with a water-air mixture with a constant air flow of 0.015 m³/(cm²⋅c) and a water flow rate of 0.0055 l/(cm²⋅s) for 420 s, subsequent exposure of the wheel to air and leave.

EFFECT: improved wear resistance of the working layer of the rim and mechanical properties, along with the disc portion of the wheel.

1 cl, 4 tbl