Based on the finite element method the distribution of thermo-mechanical plastic strain of high carbon steel (0. 73% ~0. 77%C) casting slab during soft reduction process has been simulated and calculated by using ANSYS software

the effect of reduction in height- 2 mm + 2 mm

3 mm + 3 mm and 2 mm + 2 mm + 2 mm at defined segments on plastic strain of reduction sector and location is analyzed and the simulated results are verified at casting worksite. The results show that the plastic strain simulated values coincide with the measured values ； during hot deforming process the equivalent strain at center of slab is max

that at surface flows

and the equivalent strain at 1/4 of

slab thickness is min； with increasing the reduction in height and reduction rate the thermo-mechanical plastic strain increases

and the reduction mode with 3 mm +3 mm has better reduction effect. Pilot production results show that compared with soft reduction 1. 5 mm + 1.5 mm + 1.5 mm at three segments (6

#

sector

7

#

sector and 8

#

sector) before optimization

the slab center segregation and center porosity are respectively 2. 0 rating

with soft reduction 2. 2 mm +2. 3 mm at two segments (6

#

sector and 7

#

sector or 7

#

sector and 8

#

sector) after optimization

the slab center segregation and center porosity are respectively 0. 5 rating

it is obviously improving the quality of macrostructure of casting slab.