论文信息 - The influence of material mismatch on the evaluation of time-dependent fracture mechanics parameters

The influence of material mismatch on the evaluation of time-dependent fracture mechanics parameters

Abstract The influence of material mismatch on the stress field of uniaxial specimens and the time-dependent fracture mechanics parameters is studied in the present work. The applicability of the conventional C ∗ equation based on the load line displacement is re-examined by using the finite element method. It is found that under the extensive creep condition the C ∗ value of hard weld/soft parent metal specimen can be significantly higher than that of a single weld metal specimen, and the material mismatch has little influence on C ( t ) in small scale creep in the studied cases. It is proposed that the C ∗ formula based on the load line displacement recommended by ASTM E1457 needs to be modified to interpret the CCG behaviour of welded specimens. Candidate modification factors have been proposed.

Shan.-Tung Tu | Kee.-Bong Yoon

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