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对国产T23钢焊条电弧焊接头焊缝区显微组织进行了研究。结果表明,根部焊道焊态下的组织由等轴铁素体和粒状贝氏体组成,经740℃和760℃回火后为粒状贝氏体和条状铁素体组织,在其基体上有弥散分布的点状析出物。覆盖焊道焊态下组织由粒状贝氏体和少量铁素体组成,740℃和760℃回火时为回火贝氏体组织,在690~740℃回火后形成少量聚集的粒状物,当回火温度为760℃时该粒状物分解、消失。过热区焊态下的组织由粒状贝氏体和条状马氏体组成,回火温度在690~740℃时,晶界显现,晶粒有所长大,并有大量粒状物在晶界处出现;经760℃回火处理后,原奥氏体晶界模糊、不连续,表现为回火贝氏体和回火索氏体组织,尺寸不一的点状析出物分布于基体上。
The microstructure of weld zone of domestic T23 steel arc welded joints was studied. The results show that the microstructure of root pass weld is composed of equiaxed ferrite and granular bainite. After being tempered at 740 ℃ and 760 ℃, the microstructure is granular bainite and strip ferrite, Dispersed dot-like precipitate. Weld microstructure of the weld bead consists of granular bainite and a small amount of ferrite, tempering bainite microstructure at 740 ℃ and 760 ℃ tempering, a small amount of aggregated particles formed after tempering at 690 ~ 740 ℃, When the tempering temperature of 760 ℃ when the granular decomposition, disappear. The microstructure of the overheated zone is composed of granular bainite and martensite. When the tempering temperature is in the range of 690 ~ 740 ℃, the grain boundaries appear, the grains grow up, and a large number of granular particles exist at the grain boundaries Appeared; After the tempering at 760 ℃, the original austenite grain boundaries fuzzy, discontinuous, showing tempered bainite and tempered sorbite, size distribution of point-like precipitates distributed in the matrix.