在本研究中，采用碳膜复型技术提取析出相,在抛光后的样品表面喷碳膜。将碳膜分割成2 mm×2 mm的正方形。在4 ml HNO3 + 96 ml CH3CH2OH 混合溶液浸蚀使碳膜脱落，用铜网打捞带有析出相颗粒的碳膜，在CH3CH2OH清洗干净，放入等离子水中，用φ3的小铜网打捞碳膜。使用透射电子显微镜(附带能谱分析仪EDS)。其中图a为690MPa级焊缝金属TEM贝氏体板条，图b为690MPa级焊缝金属TEM第二相析出，图c为 690MPa级焊缝金属TEM衍射斑。

In this study, carbon film replica technology was used to extract precipitated phase, and carbon film was sprayed on the surface of polished sample. The carbon film was divided into 2 mm×2 mm squares. In 4 mL HNO3 + 96 mL CH3CH2OH mixed solution, the carbon film fell off. The carbon film with precipitated particles was fished with a copper net, cleaned in CH3CH2OH, put into plasma water, and fished with a small copper net of φ3. Transmission electron microscope (EDS) was used for observation .Figure A shows TEM bainite slat of 690MPa grade weld metal, Figure B shows TEM second phase precipitation of 690MPa grade weld metal, and Figure C shows TEM diffraction spot of 690MPa grade weld metal.