Influence of δ-ferrite on Creep Rupture Strength of ZG1Cr10MoWVNbN Heat Resistant Steel

Through high temperature creep rupture test and metallographic analysis for ZG1Cr10MoWVNbN heat resistant steel samples with different quenching temperature, the influence of δ-ferrite on creep rupture strength of the steel was studied. The results show that the δ-ferrite presented banded distribution in the steels, which reduced the continuity of martensite matrix and creep rupture strength of the steel, and the higher the δ-ferrite content was, and the shorter the creep rupture test time was. At the same time, because the δ-ferrite dissolved a great deal of alloying elements, which made the alloy element content of martensite matrix decrease, the solid solution strengthening and precipitation strengthening effect weaken, and the high temperature creep rupture strength of the steel decrease.