The invention provides a
smelting method of low-
sulfur and low-
boron steel. The steel comprises, by weight, 0.05%-0.18% of C, 0.10%-0.35% of Si, 1.10%-1.60% of Mn, no more than 0.020% of P, no more than 0.003% of S, 0.010%-0.050% of Nb, 0.008%-0.025% of Ti, no more than 0.30% of Ni, no more than 0.20% of Mo, no more than 0.25% of Cr, no more than 0.0005% of B, and 0.010%-0.050% of Als. The
smelting process includes a converter, an LF furnace, an RH furnace and CC. Pretreatment for desulfuration is not needed, the carbon content of steel discharged out of the converter is slightly decreased toreduce
molten steel w[B], low-B alloys such as
manganese metal and mid-carbon
ferromanganese are added, liquid cast waste
slag is used, and the quantity of recovered liquid cast
slag is controlled, sothat rapid slagging and desulfuration are guaranteed, and the quantity of B dragged into
slag is reduced; the LF furnace only adopts aluminum wire deoxidation, and a large quantity of
argon is blownfrom the bottom to achieve stirring, so that the probability that boric
oxide in the slag is reduced and
molten steel enters the slag is lowered while the
sulfur content in the
molten steel is decreased; and when the
sulfur content in the molten steel reaches a required
sulfur content, the
argon blown from the bottom is regulated to be weak, stirring is conducted to reduce the quantity of added B,and an obtained finished products meets w[S]<=0.003 and w[B]<=0.0005.