The invention relates to a post-
forging dehydrogenation annealing technology of a
chromium-containing high-
nickel alloy steel forged piece. The technology comprises the specific steps of after
forging, slowly cooling the forged piece to 500 to 700 DEG C, keeping the temperature, increasing the temperature with full power to a temperature 100 to 150 DEG C above a complete austenitizing temperature, keeping the temperature, cooling to a temperature 50 to 100 DEG C below a
martensite transformation starting temperature, and keeping the temperature for a short time; increasing the temperature to a high-temperature
tempering zone at the speed of 30 to 60 DEG C / h, keeping the temperature, after temperature keeping, carrying out furnace cooling to 400 DEG C at the speed of 30 to 60 DEG C / h, and carrying out furnace cooling to a temperature 10 to 50 DEG C below a
martensite transformation ending temperature at the speed of 10 to 30 DEG C / h; and increasing the temperature to the high-temperature
tempering zone at the speed of 30 to 60 DEG C / h, keeping the temperature, after temperature keeping, carrying out furnace cooling to 100 to 150 DEG C at the speed of 10 to 30 DEG C / h, taking the forged piece out of a furnace, and carrying out
air cooling. According to the post-
forging dehydrogenation annealing technology of the
chromium-containing high-
nickel alloy steel forged piece, the problems that annealing and
dehydrogenation are difficult to carry out on the
chromium-containing high-
nickel alloy steel forged piece through a conventional method, and ultrasonic flaw detection defects are caused by white dots of forged pieces with relatively large specifications are solved better.