The invention relates to a high-strength complex-phase hot-rolled
wire rod for a 1960MPa-grade stranded wire and a manufacturing method of the high-strength complex-phase hot-rolled
wire rod. After high-carbon components containing trace B are designed, rolled and spun into a
wire rod, online
molten salt rapid
quenching treatment is carried out, and the wire rod is firstly subjected to front-section
molten salt treatment, so that the wire rod is cooled at the
cooling speed of greater than or equal to 36 DEG C / s and enters a
bainite and
pearlite mixed phase region from an
austenite state; the method comprises the following steps:
quenching a steel wire rod to form a structure mainly comprising quenched
bainite and a sorbite structure, carrying out rear-section
molten salt treatment on the steel wire rod, increasing the molten salt temperature, promoting isothermal
tempering of the quenched
bainite and the sorbite structure, and carrying out roller way
slow cooling to prepare the hot-rolled steel wire rod of which the microscopic structure comprises a complex-phase structure consisting of tempered sorbite, tempered bainite and ferrite, the
composition system can be simplified, the strength and
plasticity matching and rapid production of the wire rod are considered, the tensile strength is 1330-1380 MPa, the
percentage reduction of area is 35%-40%, and the wire breaking risk in the
wire drawing and twisting process of the stranded wire steel can be reduced.