Abstract: The mechanical properties , creep rupture strength, creep damage and characteristics of interfacial failure of dissimilar welded joint between martensite (9Cr1MoVNbN) and bainite steel (12Cr2MoWVTiB) are investigated by means of argon gas shielded tungsten pulsed arc welding, high temperature accelerated simulation, creep rupture, mechanical properties test. The research results indicate that the interfacial creep damage of overmatched and undermatched welded joint is serious, and the reductions of mechanical properties are obvious, the failure tendencies are higher than that of medium welded joint. The creep rupture strength of medium matched joint is almost the same as that of undermatched joint, and the creep rupture strength overmatched joint is the least one, therefore, it is reasonable that the medium matched is used for dissimilar welded joint between martensite and bainite steel.

Key words: Bainite heat-resistant steel, Dissimilar metal welded joint Interfacial failure, Martensite heat-resistant steel