The production flow sheet of 16MnCr5 cold heading steel for automobile engine valve tappet is 80 t top and bottom combined blown converter→LF + RH refining→325 mm x 280 mm bloom continuous casting→high-speed wire rolling. 16MnCr5 steel is successfully developed by using basicity 4. 8 refining slag (/% ：54. 5CaO

28. 5A1

2

O

3

11. 2SiO

2

6. 2MgO

0.6FeO + MnO)

to cancel calcium treatment process

cast billet surface quenching technology

finishing rolling at 880 ~900℃; and coiling temperature at 850 ~ 870 °C. The inspection results show that the metallographic structure of Φ30 mm wire rod is uniform ferrite + pearlite with grain size rating 8

the reduction of area is 71. 1 % ~ 72. 5%

1/3 cold upsetting is qualified. The oxygen conten

t is 0.0010% ~0.0012%

and the N content is 0.004 5% ~0. 004 7%

the size of inclusions is all within 10

μm

and there is no Ds type inclusions. The inclusions are mainly single magnesium-aluminum spinel inclusions. The wire rod has good plastic deformation capacity and high purity

to meet the customer

s requirements.