低合金钢冶炼过程增氮行为分析

为提高中厚板系列低合金钢氮含量控制水平,从热力学、动力学角度全面分析冶炼过程增氮行为,并结合相关试验对影响钢液增氮的因素进行分析。结果表明,氮在钢液中的溶解度与温度、氮分压以及合金成分有关;气泡—钢液面上的吸附化学反应为限制性环节;当钢液中w(O)≥0.04%或w(S)≥0.06%,钢液吸氮基本停止;当转炉全程底吹氮强度不超过0.025 m3/(min·t)时,转炉终点氮含量可控制在10×10-6以内。

Behavior Analysis of Nitrogen Content Increasing in Low Alloy Steel Smelting Process

In order to improve the level of nitrogen content control of low alloy steel, the paper analyzed the behavior of nitrogen content increasing from the perspective of thermodynamics and kinetics, and illustrated the factors with related experiment. The results show that, the nitrogen solubility in liquid steel relate to temperature, nitrogen partial pressure and alloy composition;bubbles-liquid steel surface chemical reaction is restrictive link; when w（O） ≥0.04% or w（S） ≥0.06% , the increasing nitrogen process of liquid steel stopped; when the whole strength of bottom blowing nitrogen of BOF is no more than 0.025 m^3/（min·t）, nitrogen content of converter can be controlled within 10×10^-6.