Analysis of the microstructure near the crack tip of ASME Gr.92 steel after creep crack growth

► Multiaxiality of stress causes Type IV failure in high Cr steel. ► The multiaxiality of stress and stress is higher at the region near crack tip. ► Recovery of dislocation structure was rapid near crack tip. ► Coarsening of M23C6 carbide was promoted near crack tip during creep crack growth.