热变形对高铌低碳钢奥氏体^→铁素体等温转变影响研究

来源期刊：钢铁2010年第10期

论文作者：曹建春 周晓龙 何寒 陈文 刘清友 雍岐龙

文章页码：70 - 74

关键词：高铌低碳钢； 热变形； 奥氏体^→铁素体等温相变

Key words：high niobium low carbon steel； hot deformation； austenite to ferrite isothermal transformation

摘    要：针对热变形对铌质量分数为0.17%的低碳钢的奥氏体^→铁素体等温相变动力学的影响,通过热模拟试验,分析未变形、875℃变形20%和30%条件下奥氏体向铁素体700℃等温转变的动力学,讨论了热变形和铌对奥氏体^→铁素体等温相变的影响机制。研究结果表明:热变形主要通过缩短相变孕育期来加速奥氏体^→铁素体等温相变;高铌钢奥氏体^→铁素体等温转变是2阶段机制,即相变初期铁素体转变率低,第2阶段相变速率高,剩余的奥氏体很快转变为铁素体。

Abstract: Using thermal simulation tester,austenite to ferrite isothermal transformation for a low carbon high niobium steel with and without hot deformation was investigated.The curves of austenite to ferrite isothermal transformation at 700 ℃ for the tested steel were obtained in un-deformation,deformation 20% and 30% at 875 ℃,respectively.Influence of hot deformation and niobium on austenite to ferrite isothermal transformation was discussed.The results show that the ferrite transformation is accelerated by hot deformation,because incubation period of the transformation is shortened by hot deformation,and the kinetics of austenite to ferrite isothermal transformation for high niobium steel is two stages that are ferrite transformation rate is lower in the first period and is higher in the second half.