Creep-Fatigue Crack Growth at CrMo Steel Weld Interface

CrMo강 용접계면균열의 크리프-피로 균열성장거동

  • Published : 2000.12.01


Creep-fatigue crack growth behavior was experimentally measured particularly when a crack was located in the heat affected region of lCr-5Mo steel. Load hold times of the tests for trapezoidal fatigue waveshapes were varied among 0, 30, 300 and 3,600 seconds. Time-dependent crack growth rates were characterized by the $C_r$parameter. It was found that the crack growth rates were the highest when the crack path was located along the fine-grained heat affected zone(FGHAZ). Cracks located in other heat affected regions had a tendency to change the crack path eventually to FGHAZ. Creep-fatigue crack growth law of the studied case is suggested in terms of (da/dt)$_{avg}$ vs. ($C_t$)$_{avg}$ for residual life assessment.


Creep-Fatigue Crack growth;Weld Interface;HAZ;Life Assessment


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