Abstract: In order to optimize the LF refining process of low carbon Al-killed steel,the effects of LF light treatment,LF refining (without calcium treatment) and LF refining + calcium treatment on inclusions,product performance,cost and production process were investigated.The results show that the typical inclusions in hot coil samples with LF light treatment are aluminate + MnS composites,and the typical inclusions in hot coil samples with LF refining are aluminate + CaS composites.The oxygen content in hot coil samples are basically the same under different LF refining ways,and there is no significant difference in mechanical properties.LF light treatment leads to good cleanliness and low cost,but tends to cause stopper rising and nozzle clogging during continuous casting.It is concluded that LF refining (without calcium treatment) should be adopted in the production of low carbon Alkilled steel,and LF light treatment should be considered when the production is small or at the end of casting.

Key words: LF refining, low carbon aluminum killed steel, inclusion, calcium treatment