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利用ＴＥＭ考察了钢中贝氏体铁素体／奥氏体相界面台阶结构及奥氏体精细结构。用ＴＥＭ温台发现在贝氏体增厚过程中新形成的贝氏体中存在奥氏体预存孪晶；在贝氏体铁素体／奥氏体相界面存在台阶结构，但台阶阶面可对应于母相奥氏体中孪晶面或层错面，表明台阶的阶面为共格的滑移界面。因而贝氏体铁素体／奥氏体相界面可通过界面台阶沿面缺陷进行保守滑移，贝氏体长大具有滑移切变特征。根据实验结果提出了贝氏体二次层错切变模型及组织形貌示意图。
TEM was used to investigate the bainitic ferrite / austenite interface structure and austenite structure in steel. Precipitation of pre-existing austenite in bainite formed during bainite thickening was found by TEM station. In the bainitic ferrite / austenite phase, there was a step structure, but the step surface could be Corresponding to the twin phase or the staggered surface in the parent austenite, it is indicated that the stepped surface is a coherent sliding interface. As a result, the bainitic ferrite / austenite interface can be conservatively slipped through the interfacial step along the surface defects, and the bainite grows with slip shear characteristics. Based on the experimental results, the model of bainitic secondary layer shear failure and the morphology of the microstructure were proposed.