Analysis of creep crack growth behavior of P92 steel welded joint by experiment and numerical simulation

Two-parameter characterization of constraint effect induced by specimen size on creep crack growth

“…The observed effect is not due to an increase in the creep crack resistance properties of the material itself, but due to variations of crack tip stress states. The creep crack growth in P92 steel are mainly caused by the creep damage accumulation which presents the nucleation and growth of creep voids and micro-cracks [28].…”

“…In Ref. [28], it was found that if the C * values accorded with the validity criteria in ASTM E1457, the variation of the initial K values had no effect on the relationship between creep crack growth rate and C* in the steady creep crack region but only affected the initial creep crack growth region. length and non-dimensional time t/t f where t is the current time of load application and t f is the life of creep crack growth for each specimen, respectively.…”

“…The smallest element size is adopted to match with the experimentally observed average grain size of P92 steel. Previous works have demonstrated that this size not only can eliminate mesh dependency effects but also can provide an accurately predicted creep crack rate [28,31].…”

Numerical investigation of creep crack initiation in P92 steel pipes with embedded spherical defects under internal pressure at 650°C

“…Table 2 lists the geometric and loading parameters for the current study. The wall thickness of the pipe, T, is fixed at 30 mm for all the models and four internal pressures (p = 28, 30, 33, and 35 MPa) are applied according to the general service pressure of USC power plants pipes ( It should be noted that in our previous publications [25,26], experiments using standard uniaxial specimens and compact tension specimens have been conducted and the results obtained through the FE methods are in good agreement with the data of creep tests. Therefore, all the creep damage parameters and FE results are reliable.…”

Stress state and stress‐induced microstructural evolution around the crack tip of G115 steel after dwell‐fatigue crack propagation

“…Martensitic steels with 9% to 12% chromium show excellent elevated‐temperature mechanical properties, have good weldability, are easy to inspect, and have sufficient resistance to corrosion cracking and oxidation . Meanwhile, these steels are less expensive and have lower thermal expansion and larger thermal conductivity compared with Ni‐based alloys or austenitic steels . Therefore, they are good candidate materials for ultra‐supercritical (USC) power plants, which demand high temperature and pressure.…”