A method for manufacturing spring steel without ferrite decarburization

摘要

The fatigue strength superior and is provided with a spring wire rod production method STEEL no ferrite decarburized layer.; The present invention is, by weight%, carbon (C): 0.4 ~ 0.6%, silicon (Si): 1.3 ~ 1.6%, manganese (Mn): 0.5 ~ 0.7%, chromium (Cr): 0.4 ~ 0.7%, the balance Fe and the billet of the composition at room temperature with unavoidable impurities were heated to 1000 ℃ 120-150 minutes, followed by the step of rough rolling and then extracted from 980~1000 ℃; After the crude rolled billet intermediate finish rolling was cooled to 830~850 ℃, the method comprising rolling the final re-cooled to 800~830 ℃; Step takes after the finish rolling, the wire rod was cooled to 730 ~ 770 ℃ volume; And the step of air-cooling the wire rod wound around a coil, since the ambient temperature and cooling to 720 ℃; is configured to include a.