形变诱导铁素体逆相变过程中的组织及取向变化

Microstructure and Orientation Change During Inverse Transformation of Deformation Induced Ferrite

通过对普碳钢Q235在Gleeble1500热模拟机上变形后的微观组织分析,研究了组织中形变诱导的铁素体在变形后保温阶段转变为奥氏体的逆相变现象;并利用背散射电子衍射(EBSD)技术分析了晶粒取向变化。结果表明,在变形后的保温过程中,形变诱导的铁素体先逆相变为奥氏体,同时伴随着诱导铁素体晶粒的长大;然后随着变形后保温时间的延长,逆相变后的奥氏体由马氏体相变逐渐过渡到铁素体的平衡转变,相应地铁素体由具有少量亚结构的形变诱导铁素体逐渐转变为具有较多亚结构的先共析铁素体。

The inverse transformation of deformation induced ferrite in plain low carbon steel Q235 during temperature holding after deformation was performed Gleeble 1 500 in and observed metallographically. The grain orientation was determined by orientation mapping of EBSD technique. The results showed that the deformation induced ferrite inverse transformed to austenite and grains growted within holding time after deformation. Then inversed austenite transformed in martensitic first, and later to ferrite by equilibrium transformation with increasing holding time. The ferrite changed from deformation induced ferrite with a little of metastrueture to proeutectoid ferrite with more metastructure.