55SiCr弹簧钢表面脱碳的研究

SURFACE DECARBURIZATION OF SPRING STEEL 55SiCr

研究了在2%残氧下,加热温度和时间对弹簧钢55SiCr脱碳层深度和组织形貌的影响规律,并运用菲克定律讨论了脱碳层深度与温度、时间的定量关系。结果表明,55SiCr钢在500～1 200℃保温30 min后,总脱碳层深度随着加热温度的升高而增加,没有出现全脱碳;在950℃和1 150℃保温5～80 min,随着保温时间的延长,脱碳层深度呈增大趋势。相对于加热时间而言,加热温度对脱碳层深度的影响更明显。

With the oxygen content of 2%, the effect of heating temperature and holding time on the depth of total decarburization during heating process of spring steel 55SiCr was studied. The morphology evolution of mierostructure was analyzed during decarburization. The quantitative relationship between the depth of total deearburization and heating conditions was discussed by using Fick＇s second law. Results showed that the depth of total decarburization increased gradually with the increasing temperature when 55SiCr steel was heated within 500 - 1 200 ~C for 30 min, and no ferrite decarburization layer appeared in this condition. The depth of total decarburization increased with the increasing soak time at 950 ℃ and at 1 150℃. However, the depth of total decarburization was more sensitive to heating temperature than to the holding time.