Abstract: The welding process with tungsten-arc inert (argon)-gas (TIG) backing, shielded metal-arc welding (SMAW) covered electrode filling and capping on P91 steel tube (/%: 0. 09C, 0.45Si, 0. 32Mn, 8. 9Cr, 0.95Mo, 0. 21V, 0. 78Nb, 0.014A1, 0. 05N) has been carried out by using ER90S-B9 welding wire and covered electrode (/%: 0. 08 ~0. 12C, 0.4~0.6Si, 0.5 ~1.4Mn, 8.5 ~10.5Cr, 0.85 ~1. 15Mo, 0. 18-0.29V, 0.06~0.10Nb, ≤0.015A1, 0. 03 ~0. 07N). Results show that the welded joint of P91 steel tube without crack, sla^ inclusions , crater and blowhole etc welding seam defects, the structure of welding seam is tempered sorbite with tempered martensite in partial region and the structure of base metal and heat affected zone is tempered sorbite； of welding joint the mechanical properties are tensile strength R_m 653 ~ 665 MPa, yield strength R_p0.2 497 〜504 MPa, elongation A 21.8% ~ 22, 9% , and impact energy 63. 8 ~77. 2 J all meet the requirement of standard GB5310-2008 and AMSE SA 335-2007.

摘要： 通过ER90S-B9焊丝和焊条(/%:0.08~0.12C,0.4~0.6Si,0.5~1.4Mn,8.5~10.5Cr,0.85~1,15Mo,0.18~0.29V,0.06~0.10Nb,≤0.015A1,0.03~0.07N)对P91钢管(/%:0.09C,0.45Si,0.32Mn,8.9Cr,0.95Mo,0.21V,0.78Nb,0.014Al,0.05N)进行氩弧焊打底、焊条电弧焊填充及盖面焊接。结果表明,P91钢焊缝无裂纹、夹渣、弧坑、气孔等缺陷,焊缝组织为回火索氏体,部分区域为回火马氏体,母材和热影响区为回火索氏体;接头的抗拉强度R_m653~665 MPa,屈服强度R_p0.2;497~504 MPa,伸长率A 21.8%~22.9%,冲击功63.8~77.2 J,均满足GB5310-2008及AMSE SA335-2007标准要求。

关键词: 马氏体耐热钢P91, 钢管, 焊接接头, 组织, 力学性能