PSI - Issue 13

Yinghao Cui et al. / Procedia Structural Integrity 13 (2018) 1291–1296 Author name / StructuralIntegrity Procedia 00 (2018) 000 – 000

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4. Simulation Results 4.1. Effect of wedging stress on creep strain at crack tip

In surface scratch stage, the creep strain under wedging stress, external load and joint action of wedging stress and external load is shown in Fig.2. Fig.2 indicates that the creep strain produced by wedging stress is bigger than the creep strain produced by external load. And the biggest creep strain appears in the 0° position. Therefore, the contribution of wedging stress to the creep strain at the crack tip is important and can not be ignored in the surface scratch stage.

Fig.2 Creep strain under wedging stress, external load and joint action

Fig.3 Creep strain under wedging stress, external load and joint action The creep strain under wedging stress, external load and joint action of wedging stress and external load when crack length is 5 μm is shown in Fig. 3. Fig.3 indicates that the creep strain produced by wedging stress is a little larger than that the creep strain produced by the external load. The biggest creep strain also appears around the 0° position.

Fig.4 Creep strain under wedging stress, external load and joint action The creep strain under wedging stress, external load and joint action of wedging stress and external load is shown when crack length is 50 μm is sh own in Fig.4. Fig.4 indicates that the creep strain produced by wedging stress is gradually less than that the creep strain produced by the external load. The biggest creep strain also appears in the 0° position.