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为提高电站锅炉过热器铁素体－奥氏体异种钢焊接接头的高温蠕变断裂强度和服役寿命，设计了专用的镍基填充材料及组合焊接接头。通过对不同焊缝接头的高温蠕变力学试验、焊缝界面组织变化分析、碳扩散和热应力的测试分析，认为在高温低应力的条件下，接头焊缝界面及热影响区碳元素扩散迁移和碳化物聚集是影响接头蠕变断裂强度的重要原因；用镍基焊缝作为过渡段的组合接头具有较小的界面热应力和较高的持久强度。
In order to improve high temperature creep rupture strength and service life of ferritic-austenitic dissimilar steel welded joints of power plant boiler superheater, a special nickel-based filler material and a combination welded joint were designed. Through the high temperature creep mechanics test, the weld interfacial microstructure change analysis, the carbon diffusion and the thermal stress test analysis of different weld joints, it is considered that under the condition of high temperature and low stress, the diffusion and migration of carbon in the weld interface and the heat affected zone And the carbide agglomeration are the important factors that affect the creep rupture strength of the joint. The nickel-based weld joint as the transitional joint has less interfacial thermal stress and higher lasting strength.