冷却速率对低碳钢线材表面氧化皮微观结构的影响

采用X射线衍射与Mossbauer谱分析相结合，研究了不同冷却速率下低碳钢表面形成氧化皮的微观结构；借助磁力显微镜的抬高模式测量氧化皮的磁畴图，获得了氧化皮内Fe₃O₄的分布形态及冷却速率对其变化的影响.结果表明：快速冷却时氧化皮中Fe₂O₃的含量减少；FeO与Fe₃O₄的比例增大；化学计量的FeO含量和Fe₃O₄的缺陷程度也随冷却速率的变化而变化.氧化皮的相组成和氧化皮内Fe₃O₄的分布形态是影响氧化皮性能的主要因素.

Influence of Cooling Rate on Microstructure of Oxide Scales Formed on Low Carbon Steel Wires(Chinese)

Oxide scales were prepared by cooling low-carbon steel wires at different rates and the microstructure was investigated by X-ray diffraction (XRD) and Mossbauer spectroscopy. The distribution of Fe₃O₄ in the oxide scale was obtained using Magnetic Force Microscope (MFM), through which the influence of the cooling rate on the distribution of Fe₃O₄ was studied. The results showed that when low carbon steel wires are rapidly cooled, the content of Fe₂O₃ in the oxide scale decreases while the content ratio of FeO to Fe₃O₄ increases. At the same time, the content of stoichiometric FeO and the defect concentration of Fe₃O₄ can also change with different cooling rates. The phase composition of the oxide scale and the distribution of Fe₃O₄ are the main factors that affect the properties of the oxide scale.