Calcium treatment method of ultra-low-carbon and high-aluminum steel

The invention discloses a calcium treatment method of ultra-low-carbon and high-aluminum steel. The calcium treatment method mainly solves the technical problem that when an existing slab caster casts ultra-low-carbon and high-aluminum steel comprising 0.001%-0.01% of carbon and 0.1%-0.3% of aluminum, a continuous casting water gap is knotted. The calcium treatment method of ultra-low-carbon and high-aluminum steel comprises the following steps that firstly, decarburization is carried out on molten steel in an RH furnace inlet station for 10-20 min under the vacuum degree of 270 Pa; secondly, silicon is adopted for decarburized molten steel for deoxidation, circulation is carried out for more than three minutes, an appropriate number of aluminum blocks are added to the component design range, circulation is carried out for more than five minutes under the situation that the circular flow is 1,600-3,000 L/min, and Alt and Als in the detected molten steel are sampled; thirdly, calcium iron alloy blocks are added through an RH furnace burden bin to carry out calcium treatment on molten steel, and the vacuum degree is reduced to 10-20 KPa; and after the calcium iron alloy blocks are added, circulation is carried out for more than three minutes in the state that the circular flow is 1,400-2,500 L/min. Compared with a common calcium treatment technology, the continuous casting water gap is effectively prevented from being knotted.