The test new type steel 616 containing Ce (/% : 0. 23 ~0. 25C

0.73 - 0. 78Si

1. 64 ~ 1. 70Mn

0.003 ~0.005S

0.016-0.020P

0.051 ~0.061Ti

0. 026 ~0.028Nb

0.002 0 -0.0030B

0~0.302Ce) is melted by a 10 kg vacuum induction furnace

rolled to 5mm thickness plate

water-quenched at 900 ℃. and tempered at 600 °C. The effect of Ce content in steel on structure and mechanical properties of plate of steel 616 has been studied by universal tensile testing machine

optical microscope

scanning electron microscope etc experimental instrument. Results show that as the Ce content in steel is 0. 096%

the refinement of grain in plate of steel 616 is obvious and the sulphide in steel is modified from long strip to spheroid

it is available to increases the tensile strength and toughness of steel plate

the tensile strength of 0. 096% Ce plate increases to 779 MPa from 681 MPa of non-adding Ce plate ； as the Ce content further increases the more refinement of grain in plate is not obvious and the amount of inclusions in steel increases

with Ce content 0. 302% the tensile strength of plate decreases to 712 MPa.