CO_2含量对高强钢MAG焊焊缝金属低温韧性的影响

Effect of CO_2 content on low-temperature toughness of weld metal of high strength steel in MAG welding

通过调节保护气体中CO2的含量,研究了保护气体氧化性对高强钢焊缝金属低温韧性的影响规律,同时分析了这种影响规律的作用过程。试验结果表明,随着保护气体中CO2含量增加,粒状贝氏体组织在焊缝金属中含量增加,焊缝金属低温韧性降低;当保护气体中CO2含量较少时,焊缝金属组织以针状铁素体为主,焊缝金属具有较高的韧性水平。

In the article, the effect of shielding gas oxidizability on low-temperature flexibility of weld metal of high strength steel were investigated by changing carbon dioxide content. The results show that the low-temperature toughness of weld metal decreased with the increase of carbon dioxide content. When the carbon dioxide content is low, the microstructure of weld metal is mainly acicular ferrite, the low-temperature toughness of weld metal is in high level, with the increase of carbon dioxide content, granular bainite increases, which decreases the low-temperature toughness.