钢中Si、P元素配比对其氧化特性的影响

为了获得高表面质量的冷轧产品,采用场发射SEM、EPMA和高温激光观察等方法,系统研究了钢中w(Si)/ w(P)不同配比对氧化铁皮形成、起泡和铁橄榄石相(Fe₂SiO₄)液化温度的影响,明确了w(Si)/ w(P)不同配比条件下界面元素富集及其氧化特性。结果表明:随着w(Si)/ w(P)的提高,试样低温抗氧化能力提高,氧化增重速率峰值出现的温度逐渐提高,当w(Si)/w(P)为12时,氧化峰值温度提高至1 170 ℃,氧化增重速率峰值也急剧提高到1.08%/min;随着w(Si)/ w(P)的提高,表层氧化铁皮鼓泡现象明显减轻;高温激光观察试验发现,随着w(Si)/ w(P)的降低,氧化铁皮与基体界面处的Fe₂SiO₄相液化温度逐渐降低,w(Si)/ w(P)为3条件下界面Fe₂SiO₄相于1 080 ℃开始出现液化现象。因此,添加P元素是降低 Fe₂SiO₄相液化温度的一种有效而实用的方法,同时还可显著降低氧化铁皮的粘附力。

Influence of Si and P mass fraction ratio on oxidation characteristics of steel

In order to obtain cold rolled products with high quality surface, adopting field emission SEM, EPMA and high temperature laser observation methods, the effects of different mass fraction ratios of w(Si)/w(P) in steel on the oxide film formation, blistering and liquefaction temperature of fayalite phase (Fe₂SiO₄) were systematically studied. The interfacial element enrichment and oxidation film characteristics under different w (Si)/w (P) ratios were determined. The results showed that with the increase of w (Si)/w (P) ratios, the antioxidant capacity of samples at low temperature were improved; the temperature of the peak oxidation weight gain rate was gradually increased. When w (Si)/w (P) ratios were 12, the peak oxidation rate temperature was increased to 1 170 ℃ and the peak oxidation weight gain rate also was increased sharply to 1.08%/min. With the increase of w (Si)/w (P) ratios, the surface scale blistering phenomenon were significantly reduced.The high-temperature laser observation experiment found that with the decrease of w (Si)/w (P) ratios, the Fe₂SiO₄ phase liquefaction temperature was gradually decreased, under the condition of w (Si)/w (P) ratios were 3, the Fe₂SiO₄ phase liquefaction temperature was 1 080 ℃. The addition of P element is an effective and practical method to reduce the melting temperature of Fe₂SiO₄ phase, and at the same time, it can significantly reduce the adhesion force of the oxidation scale.