Time-dependent crack growth behavior of a nitrogen strengthened Ni-Fe-Cr-Nb- N alloy 120

摘要

Creep and creep crack growth behavior of alloy 120 (HR120(trademark)) were studied through the time-dependent fracture mechanics characterization at 871 C (1,600 F). The material was tested under tensile, creep and creep crack propagation conditions to develop an understanding of time-dependent behavior under variable stresses at elevated temperature. The resulting properties were also compared with those of alloy 333 (RA333(trademark)) and alloy (HR160(TM)) previously obtained using the same testing and data processing methods. Results show that at elevated temperature, alloy 120 and alloy 333 had little primary creep while alloy 160 demonstrated significant amount of primary creep. Comparison based on creep energy consumption rate indicates that creep crack growth resistance of alloy 120 is greater than that of alloy 333, but a little less than that of alloy 160.