Cause analysis and improvement of SWRH82B wire rod drawing fracture

SWRH82B wire rod for pre-stressed steel strand fractured while drawing.The process of smelting,continuous casting and rolling was analyzed.Quality requirements of SWRH82B wire rod is put forth:carbon mass fraction fluctuation is less than 0.03%,chemical composition is uniform,inclusion is deformable such as MnS,SiO2 etc.,and little aluminate,size should be less than 30 μm.Billet for SWRH82B wire rod was examined,ground and careful finishing,to control steel composition uniformity,liquid steel overheating degree,segrgation while continuous casting,sorbite ratio in wire rod reached over 85%,abnormal microstructure such as wire rod central cementite and martensite was controlled.The main reason that causing wire rod drawing fracture are as follows:aging period is short,area reduction is low,scar,acieration occurs in the surface,network cementite and martensite occur in wire rod center and surface scratch etc.Improved measures were taken aiming at the corresponding reasons.Wire rod percentage of pass are raised greatly.