通过热-力耦合方法实现低碳微合金钢奥氏体的亚微米化

摘要

以两种成分不同但组织均为温轧铁素体和珠光体的低碳微合金钢为研究对象,通过合理选择加热奥氏体化过程中的变形参数,实现了奥氏体晶粒的细化；结合真应力-真应变曲线以及显微组织对其细化机理进行了分析.结果表明:通过热-力耦合的方法成功得到了亚微米晶奥氏体晶粒；奥氏体动态相变、铁素体动态再结晶以及变形过程中应变硬化等机制的竞争耦合作用对奥氏体的亚微米化过程至关重要.%Taking two kinds of low carbon steel with different chemical compositions and same microstrucute of warm-rolled ferrite and pearlite as research objects,the austenitc was refined by selecting reasonable deformation parameters during austenitizing,and the refinement mechanism was analyzed by combing the true stress-true strain curve and microstructure.The results show that submicron crystal austenite grains were prepared successfully by thermal-mechanical coupling method.It was found that the cooperative competition of dynamic austenite transformation,dynamic recrystallization of ferrite and work hardening during deformation was crucial for submicron-crystallized austenitc.