Un-homogeneity of deformation is the driving force on pencil-tip shaped fracture of cord steel 72A during cold drawing. The coarse proeutectoid ferrite and thicker cementite lamella at center of wire are source of crack during rough drawing; and the crack produced by center segregation often occurs during middle-drawing.With controlling center carbon segregation index of cast billet ≤ 1.1

using ≥ 15℃/s quick cooling process before phase transformation

control- ling cooling at phase transformation zone 600～620 ℃ similar isothermal transformation to obtain proeutectoid ferrite content ≤0.8%

uniform sorbite structure being up to 90%

the pencil-tip shaped fracture of 72A steel wire during straight-line drawing is basically avoided.