The process for cold-drawn wire of steel 0Cr13C (/% : 0.02C

0.32Si

0.18Mn

0.016P

0.002S

12.25Cr

0.0140N) is φ5.5 mm hot-rolled rod annealed at 680~700°C -cold-drawing to φ2.0 mm coil-hydrogen annealing (HA) -cold-drawing to φ0.70 mm wire-HA-cold-drawing to φ0.3 mm wire. With analysis on composition

fracture

structure and mechanical properties of steel

it is obtained that the φ5.5 mm annealed hot-rolled coil has mixed grain structure and higher tensile strength led to non-homogeneous deformation and wire fracture during cold-drawing process. Test results of annealing at 720~760℃ show that with increasing annealing temperature the tensile strength of steel 0Cr13C decreases

the tensile strength of φ5.5 mm rod annealed at 720°C

740°C and 760℃ is respectively 471~ 503 MPa

417~448 MPa and 317~417 MPa. The production results show that by increasing annealing temperature of φ5.5 mm hot- rolled coil from original 680〜700℃ for 2h to 740°C for 3~4h

average ratio of wire fracture at each cold-drawing bench decreases from 6 times/12h to 2 times/12h.