The invention relates to a high-strength complex-phase hot-rolled
wire rod for a 2200MPa-grade bridge cable and a manufacturing method of the high-strength complex-phase hot-rolled
wire rod. After C-Si-Mn-Cr chemical components are rolled and spun into a
wire rod, the wire rod is subjected to online
molten salt critical
quenching isothermal treatment, the wire rod is controlled to be subjected to front-section treatment and cooled at a
cooling speed of greater than or equal to 38 DEG C / s, and enters a
pearlite and
martensite mixed phase region from an
austenite state; the method comprises the following steps: firstly, carrying out heat treatment on
austenite to promote transformation of part of
austenite to sorbite and
martensite, then carrying out post-treatment, reducing the circulation volume of
molten salt, promoting transformation of austenite to
pearlite, carrying out isothermal
tempering, and finally carrying out roller way
slow cooling, so as to prepare a hot-rolled wire rod of which the
microstructure comprises a complex phase structure consisting of tempered
pearlite, tempered sorbite, ferrite and tempered
martensite, the
composition system can be simplified, the deteriorated structure can be effectively controlled, complex-phase structure regulation and control and high-strength plastic performance matching are achieved, the tensile strength is 1568-1603 MPa, the
percentage reduction of area is 29%-34%, and stable manufacturing of the bridge cable is facilitated.