在本研究中，先在预磨机上进行预磨，然后在150、320、600和1000号砂纸上依次水磨，在抛光机上进行机械抛光后，置于4 ml HNO3 + 96 ml CH3CH2OH混合溶液浸蚀15~25 s，采用FEI Quanta650热场发射扫描电子显微镜分析，观察贝氏体铁素体基体的形貌没有明显的变化，MA岛发生分解。

In this study, pre-grinding was carried out on the pre-grinding machine, followed by water-grinding on No. 150, 320, 600 and 1000 sandpapers. After mechanical polishing on the polishing machine, the samples were immersed in 4 mL HNO3 + 96 mL CH3CH2OH mixed solution for 15 – 25 s. The FEI Quanta650 thermal field emission scanning electron microscope was used to analyze the morphology of bainite ferrite matrix. There was no significant change in the morphology of bainite ferrite matrix, and the MA island was decomposed.