The 2311 die steel 16 ~ 80 mm plate is produced by KR desulfphrization-130 t BOF-LF-RH-300 mm cast slab-rolling-580 -610 °C tempering process. The results show that for 2311 steel (/% : C 0. 38 ~0.42

Si 0.25 ~0. 35

Mn 1.30 ~ 1.50

P≤0.020

S≤0.005

Cr 1.80 ~2.00

Mo 0.17 ~0.25

Als 0.015 ~0.045)

through alloys rational division in converter-LF-RH process

the composition hit rate of the molten steel in tundish can be improved; using weak cooling and low speed casting (0.70 ~0.75 m/min)

pit cooling and slow heating (10-12 min/cm)

the slab cracking can be avoided； with thermo-mechanical rolling control process (TMCP) +580 -610 °C tempering process

the thickness 16 - 80 mm steel plate with hardness value 28 ~33HRC

cross-sectional hardness deviation value W3HRC

metallographic organization of tempered bainite

and eliminating internal stress of microstructure can be achieved. Finally

the performance and microstructures of the steel plate can meet the requirements of 2311 pre-hardened die steel.