Wel-Ten 780A高强钢焊接接头组织和性能研究

Microstructures and properties of Wel-Ten 780A high-strength steel welded joints

通过对Wel-Ten 780A高强钢焊接接头进行了拉伸、冲击、硬度及金相组织分析研究,结果表明,采用YM-80A(ER110S-G)焊丝焊接Wel-Ten 780A高强钢时,焊接接头的抗拉强度、屈服强度较母材实测值有所降低;焊接接头具有良好的冲击性能,焊缝、热影响区的室温冲击吸收能量均高于母材;焊接接头的硬度在350HV以下,焊接热影响区存在软化区;焊缝为晶界析出先共析铁素体,晶内为针状铁素体和粒状贝氏体,焊接热影响区和母材的组织为块状铁素体和细小的珠光体、粒状贝氏体。

Microstructures and properties of Wel-Ten780A high-strength steel welded joints were investigated by tensile test,impact test,hardness test and microstructure analyzing.The results show that with YM-80A(ERl 10S-G)Wel-Ten780A welding wire,the tensile strength,yield strength of welded joint are significantly reduced,and the elongation,area reduction rate are equal to that of the base metal.Welded joints have good impact properties.Impact absorbed energy of weld and heat affected zone at room temperature were higher than that of the base metal.The hardness of welded joints was below 350 HV,and there is softening area in welding heat affected zone.The microstructure in weld is the grain boundaries eutectoid ferrite,intragranular ferrite to acicular and granular bainite,and the microstructure in HAZ and base metal is the massive ferrite and fine pearlite,granular bainite.