Microstructural changes in cast martensitic steel after creep at 620°C

Microstructural changes in the cast steel GX12CrMoWVNbN10-1-1 (Fe–0.11 C–0.31 Si–0.89 Mn–9.57 Cr–0.66 Ni–1.01 Mo–1.00 W–0.21 V–0.06 Nb–0.05 Cu–0.05 N in wt %) have been investigated after tests for long-term strength at a temperature of 620°C in the range of stresses of 120–160 MPa. Upon short-term creep (up to 5000 h), the tempered troostite structure and distribution of particles of proeutectoid constituents change insignificantly, except for...