摘要
采用光谱分析、夏比冲击、OM、SEM和EDS等方法研究了X80管线钢焊缝成分、组织和性能,并探讨了焊接裂纹形成机制。结果表明,由于焊接冶金和固态相变的作用,X80管线钢的焊缝呈现凝固和相变组织的综合特征,其微观组织为粒状贝氏体+大块状铁素体;焊缝处裂纹呈现结晶裂纹特征,其内部存在大量的非金属夹杂物;焊缝断口大部分为解理断裂,近裂纹边缘具有准解理断裂特征,冲击性能低于热影响区和母材。
Chemical composition,microstructure,mechanical properties of X80 pipeline steel welded seam were investigated by means of spectrometric analysis,charpy impact test and OM,SEM and EDS analysis,and its welding crack formation mechanism was discussed.The results show that due to welding metallurgy and solid-state phase transformation,the welded seam of X80 pipeline steel presents the comprehensive characteristics of welding solidification structure and phase transition structure,and its microstructure is composed of granular bainite and large massive ferrite;welding crack shows the crystalline crack features and there is a lot of non-metallic inclusions in it;most of welding fracture is the cleavage fracture,the near crack edge fracture possesses the characteristics of quasi cleavage fracture and the impact toughness of the welded seam is lower than that of the heat affected zone and parent metal zone.
出处
《金属热处理》
CAS
CSCD
北大核心
2015年第11期68-72,共5页
Heat Treatment of Metals
基金
国家自然科学基金(51071026)
关键词
X80管线钢
焊缝组织
焊缝裂纹
冲击性能
X80 pipeline steel
welding microstructure
welding crack
impact toughness
