VOD精炼316L不锈钢吹氮合金化的研究

用0.8 kg钢水石墨坩埚的硅钼棒炉研究了常压下氮气分压(33～100 kPa) 、吹氮时间(0～50 min) 、吹氮流量(0.3 L/min) 、钢液温度(1 773～1 833 K)对316L钢(%:0.031C、16.13Cr、10.12Ni、2.12Mo、0·028N)中氮含量的影响,并试验了在前期真空条件下1 853～1 833 K吹氮40 min、2 kPa、0.1 L/min,中期吹氮40 min、100 kPa、0.3 L/min,后期吹氮50 min、100 kPa、自然冷却至1 773 K时316L钢水的增氮行为。结果表明,钢中氮含量随着吹氮时间、氮分压的增加而增大,常压下吹氮10 min,钢液含氮量即可超过0.10%,随吹氮流量增加钢液达到饱和的时间缩短,氮的溶解度随着钢液温度的降低而升高。应用热力学和动力学模型进行了分析。

A Study on Blowing Nitrogen Alloying of Stainless Steel 316L with VOD Refining

The effect of nitrogen partial pressure (33 ~ 100 kPa), nitrogen blowing time (0 ~50 min), nitrogen rate (0. 3 L/min) and liquid temperature (1 773 ~ 1 833 K) in normal atmosphere condition on nitrogen content in steel 316L (% ： 0. 31C, 16. 13Cr, 10. 12Ni, 2. 12Mo, 0. 028N) has been studied and the behavior of nitrogen absorption in steel 316L with nitrogen blowing for 40 min, 2 kPa, 0. 1 L/min at 1 853 ~ 1 833 K in initial vacuum condition, nitrogen blowing for 40 min, 100 kPa, 0. 3 L/min in middle period and nitrogen blowing for 50 min, 100 kPa then natural cooling to 1 773 K in last period is tested by using silicon-molybdenum furnace with graphite crucible containing 0. 8 kg steel liquid. Results show that with increasing nitrogen blowing time and nitrogen partial pressure the nitrogen content in steel increases, the nitrogen content in liquid is more than 0. 10% as nitrogen blowing for 10 min in normal atmosphere, with increasing nitrogen rate the time that come to saturated nitrogen in liquid decreases and with decreasing temperature of liquid the solubility of nitrogen increases. The analysis on nitrogen absorption is carried out by thermodynamic and dynamic models.