The invention discloses a heat treatment process of a large-size 1Cr13 mandrel
forge piece, which is suitable for the 1Cr13
forge piece with the outer circle
diameter of less than or equal to phi 700mm, the
temperature difference between the outer surface and the core part of the
forge piece is reduced through a multi-step speed-limiting heating mode, and the phenomenon of forge piece
cracking caused by overlarge thermal stress in the heating process is avoided. A reasonable
quenching cooling mode is adopted, it is guaranteed that even and fine
lath-shaped
martensite is obtained after the step forge piece with the large cross section difference is quenched, and the risk that the step forge piece with the large cross section difference cracks due to the fact that
quenching structure transformation stress is too large is avoided; through a rapid cooling mode, the temper
brittleness of the 1Cr13 forge piece in the temperature range of 480-600 DEG C is effectively removed, and the failure phenomenon of
intergranular fracture of the forge piece in the using process is avoided; and after
tempering and discharging, the final temperature of the forge piece is controlled, so that the
residual stress generated by rapid cooling is effectively removed, and the stability of the forge piece is improved.