关键词: 60 t LD-LF-VD-CC-Roll, 38MnVS6易切削钢, , 工艺实践, 冶金质量

Abstract: The production process of non-quenched-tempered steel 38MnVS6 (/% ：0.36 ~ 0.40C ,0.50 ~ 0.65Si, 1.30~1.45Mn,  ≤ 0.020P, 0.045 ~0.065S, 0.10 ~0.30Cr, 0.015 ~0.030A1, ≤0.05Mo, 0.08 ~0.12V, 0.013 ~0. 019N, 0.015 ~0.025Ti) is 60 t LD-LF-VD-CC-Roll process. In order to produce 80 mm bars, the following methods would be used. The LD end point [C] is control above at 0. 01% together with [P] below at 0.015%. The basicity of LF refining slag and Al₂O₃ content are controlled at 3.0 ~ 4. 0 and 20% ~25% respectively. The S line would be fed after VD treatment to ensure [S] controlled at 0. 055% into molten steel. The low basicity mould fluxes (R = 0. 65) has been used in continuous casting process. It is necessary to controlled final temperature of rolling steel at 900 °C , and the 080 mm bar should be slowly cooled after rolling. Through the detection and analysis of 38MnVS6 bar, it was found that class A inclusions (thickness series) is grade 1.5,and the rating of center porosity is 1.5,and the grain size is grade 7. The performance of bar product is very good.

Key words: 60 t LD-LF-VD-CC-Roll, Free-Cutting Steel 38MnVS6, Process Practice, Metallurgical Quality ,