METHOD OF THERMAL TREATMENT OF CAST PARTS MADE OF LOW-ALLOYED AND CARBON STEELS Russian patent published in 2018 - IPC C21D1/78 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy and can be used in thermal cycling (TC) of pearlite-grade steels used in the oil, gas industry, car building and other branches of engineering. To increase toughness at low temperatures down to minus 60 °C perform high-temperature austenitization of the molded part at a temperature of 100–150 °C above the point Ac₃ with an exposure of 2.5–3.0 min per 1 mm cross section, then repeated heating and cooling from the intercritical interval, subsequent quenching from the intercritical interval with cooling in water, and stepped tempering with heating first to 400 °C with a shutter speed of 1.5–2 hours, and then up to 600 °C with an exposure of 3 hours.

EFFECT: invention can be used in thermal cycling (TC) of perlite steels used in the oil, gas industry, car building and other branches of engineering.

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