Base metal wire rod special for 1,420 MPa-level PC steel bar and preparation method of base metal wire rod

The invention discloses a base metal wire rod special for a 1,420 MPa-level PC steel bar and a preparation method of the base metal wire rod. The base metal wire rod is prepared from following chemical components in percent by mass including 0.27%-0.32% of C, 0.80%-1.00% of Si, 1.0%-1.20% of Mn, 0.010%-0.017% of Ti, smaller than or equal to 0.025% of P, smaller than or equal to 0.025% of S, smaller than or equal to 0.010% of Mo, smaller than or equal to 0.0060% of N, smaller than or equal to 2.0% of Si+Mn, larger than or equal to 160 of Si:N and the balance Fe and inevitable impurities. The preparation method of the base metal wire rod includes the procedures of heating, rough intermediate rolling, pre-finish rolling, precontrol cooling, finish rolling, control cooling, spinning and slow cooling. Through optimization design of the steel components and coupling control of the steel rolling process, the rolling starting temperature, the finish rolling entering temperature and the spinning temperature of steel a