异种钢熔合区马氏体脆性层的消除

Study on Elimination of Martensitic Shortness Layer for Dissimilar Steel Weld

利用磁性测定仪、光学显微镜和扫描电子显微镜 ,分析了 1Cr18Ni9Ti与15CrMo钢的焊接性能 ,研究了其接头在常温和长期高温下出现马氏体脆性层的主要因素 ,探讨了不同焊接材料和工艺对异种钢接头成分、组织和性能的影响规律 ,以及不同状态下异种钢接头马氏体脆性层宽度变化的规律 ,提出了一种在 1Cr18Ni9Ti与15CrMo接头的 15CrMo一侧的坡口表面上 ,预堆敷 8mm厚自研制的NR4 17过渡层 ,后熔敷A3 0 7复合合金的有效方法。此方法彻底消除了异种钢熔合区在常温和高温下的马氏体脆性层 ,不仅解决了氨合成塔下出口管与配管的异种钢焊接问题 ,而且对其它化工压力设备上异种钢接头的焊接具有一定的参考价值。

In this paper the weldability of 1Cr18Ni9Ti and 15CrMo steels is analysed by magnetic recongnizer and scanning electromicroscope.Main factor of forming martensitic shortness layer is discovered in the weld at normal temperature and continuous high temperature.The effect law of different welding material and technology on ingredient and microstructure and performance of joint are discussed.And change law of martenstic shortness layer conent at different state is also discussed.A effective method of pre surfaced 8 mm thick transition layer of pearlitic new R417 electrode,then depositing austenitic A307 complex alloy on 15CrMo side beveled surface in 1Cr18Ni9Ti and 15CrMo joint has been created.This method has fully eliminated martensitic shortness layer of dissimilar steel joint at the normal temperature and high temperature.It solved welding problem of pipeline joint in ammonia synthetic tower and provided some reference for joint in other chemical pressure equipment.