中碳铌微合金化钢NbC的析出控制

Precipitation control of NbC in medium carbon niobium microalloyed steel

对开坯+连轧生产出的大规格铌微合金化中碳圆钢的轧后NbC形态进行了研究分析。研究发现,中碳钢铌的质量分数为0.03%时,连铸凝固过程中会析出5μm以上的碳化铌;钢坯轧制加热温度为1 250℃左右,高温段保温时间为4 h以上时,微米级碳化铌得到固溶。

NbC morphology of carbon round steel in niobium microalloying was studied and analyzed after rolling.According to the study,when the mass fraction of niobium in medium carbon steel is 0.03%,niobium carbide above 5μm will be precipitated in the process of continuous casting solidification.When the heating temperature of billet rolling is about 1250℃and the holding time of high temperature section is more than 4 h,the solution of micron grade niobium carbide can be obtained.