脱碳时间对Fe-3%Si钢氧化层组成及形貌的影响

Effect of annealing time on oxide phases and morphology of Fe-3%Si steel surface during decarburization

脱碳退火时间是决定Fe-3%Si钢表面内氧化行为的重要工艺参数之一,继而影响着后续渗氮及二次再结晶工艺。在1 103K的退火温度及N2+H2+H2O的退火气氛下进行了脱碳退火实验,研究了退火时间对Fe-3%Si钢表面氧化行为的影响。通过傅里叶变换红外光谱仪、扫描电镜及辉光放电质谱仪观察了Fe-3%Si钢表面氧化层的演变过程,分析了氧化层内硅、氧含量分布趋势,建立了氧化层结构与氧化物含量之间的关系。实验结果表明,经过脱碳退火后,Fe-3%Si钢表面氧化物由二氧化硅和铁橄榄石组成。随着退火时间的延长,内氧化层增厚,硅元素在内氧化层中的富集程度增加。当硅钢表面氧化深度相同时,氧化物含量随退火时间的增加而增多。

Annealing time is an important process parameter to determine the oxidation behavior of Fe-3%Si steel during decarburization,and then affects the nitriding process and secondary recrystallization process.The oxidation behavior of Fe-3%Si steel with different annealing time was studied in N_2＋H_2＋H_2O at 1103 K.The evolution of oxidized layer and the relationship between structure of oxidized layer and oxide content were investigated using Vertex type Fourier transform infrared,scanning electron microscopy and Glow Discharge Spectrometer.The results show that the oxides are composed of SiO_2 and Fe_2SiO_4.With the increase of annealing time,the internal oxidation zone thickens and the enrichment of silicon increases in the oxidized layer.When the depth of oxidized layer is same,the oxides content increases with increasing annealing time.