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为掌握汽车悬架用60Si2MnA弹簧钢的铁素体全脱碳行为，利用Gleeble1500热模拟机、金相显微镜、扫描电镜和电子探针等研究了加热温度、保温时间、热轧后的冷却速率对铁素体全脱碳层形成的影响．研究结果表明，加热温度对铁素体全脱碳行为影响最大，影响区间为725～925℃，850℃对应的脱碳层厚度达到最大；保温时间和冷却速率对铁素体脱碳行为也有较大影响，脱碳层厚度与时间的平方根呈线性关系；冷却太慢会形成较厚的脱碳层，冷却速率达到0．2℃/s时，实验钢基本不会发生脱碳行为．因此，避开脱碳层峰值温度，减少在（α＋γ）两相区停留时间，均可有效阻止60Si2MnA弹簧钢的铁素体全脱碳．

The ferrite decarburization behavior of 60Si2MnA spring steel for automotive suspensions was investigated in this paper. The effects of heating temperature, heating time and cooling rate after hot rolling on the ferrite full decarburized layer was studied by Gleeble1500 thermal-mechanical simulator, optical microscope, scanning electron microscopy and electron probe. The results show that the ferrite decarburization, which has the strong temperature dependence due to phase transformation, is produced between 725 and 925 ℃. The maximum depth is found at 850℃. The heating time and cooling rate exert an important influence on decarburization. The thickness growth of decarburized layer exhibits a linear relationship with the square root of time. The thicker decarburized layer forms at slower cooling rate. The decarburization almost does not occur when the cooling rate is no less than 0.2 ℃/s. Therefore, avoiding peak temperature of decarburization, and shortening the residence time in (α+γ) two-phase region are suggested to protect against ferrite decarburization.