摘要
研究了不同强度匹配下X80级Nb-Cr钢手工焊环焊接头的显微组织和硬度。结果表明:不同强度匹配下填充层组织经过后续焊道的热处理作用,打破了焊缝柱状晶的形态,焊缝组织为针状铁素体+少量粒状贝氏体+少量先共析铁素体,粗晶区组织为粒状贝氏体+板条状铁素体;盖面层焊缝组织以针状铁素体组织为主,粗晶区组织以板条状铁素体+粒状贝氏体为主;盖面层高硬度组织板条铁素体和粒状贝氏体明显增多,硬度整体偏大。
This article has studied the microstructure and hardness under the different intensity match the Nb - Cr XSO steel of SMAW joint, the resuhs indicated that under different intensity match the filling pass microstructure through the following weld bead heat treatment, has broken the welded joint column crystals shape,weld joint microstructure is the acicular ferrite ; coarse-grained zone microstructure is granular bainite ＋ board ferrite banding. The cap weld microstructure is acicular ferrite;coarse-grained zone microstructure is board ferrite banding ＋ granular bainite. The cap welded joint does not look like the root pass and the fill pass receives the heat treatment of the following bead, the high hardness microstructure of ferrite and the granular bainite increase obviously, caused hardness of the cap allover big.
出处
《焊管》
2009年第10期9-12,共4页
Welded Pipe and Tube
