The invention relates to a high-strength complex-phase hot-rolled
wire rod for a 2300MPa-grade bridge cable and a manufacturing method of the high-strength complex-phase hot-rolled
wire rod. After Al-containing high-
carbon steel components are hot-rolled and spun into a
wire rod, the wire rod is subjected to online
molten salt critical
quenching isothermal treatment, so that the wire rod firstly passes through front-section
molten salt and is cooled at a
cooling speed of greater than or equal to 37 DEG C / s; part of the
austenite structure is transformed into a quenched
bainite and quenched
martensite mixed structure, then the temperature is increased to the sorbite phase region temperature through rear-section
molten salt heating, the untransformed
austenite is controlled to be transformed into sorbite, isothermal
tempering is conducted, and finally
slow cooling is conducted through a roller way; the hot-rolled wire rod of which the microscopic structure comprises a complex-phase structure composed of tempered
bainite, tempered sorbite and tempered
martensite is prepared, the material cost can be considered, complex-phase structure regulation and control are achieved, the strength and
plasticity matching and the structure uniformity of the wire rod are improved, the tensile strength is 1617-1656 MPa, the
percentage reduction of area is 27%-32%, and the ultrahigh-strength bridge cable can be stably produced.