Creep Properties and Microstructure of A New High Chromium Ferric Steel

The creep properties of a new high chromium ferric steel under 110, 120 and 130 MPa at 650 ℃ were investigated. Then the microstructure of the steel before and after creep was comparatively analyzed. The results show that the steel had good creep resistance. With increasing the loading from 110 MPa to 130 MPa at 650 ℃, the creep rupture time decreased from 4 500 h to 3 600 h, the creep rate increased from 7.7×10-10 s-1 to 1.1×10-9 s-1, whose creep resistance was better than that of the T91, T92 and T122 steels under the same test condition. The lath martensite of the steel disappeared completely in necking deformation area. The M23C6 carbides coarsened obviously in the uniform and necking deformation area. And a new Fe2(W, Mo) intermetallic phase formed.