PSI - Issue 16

Volodymyr Panasyuk / Procedia Structural Integrity 16 (2019) 3–10 Volodymyr Panasyuk / Structural Integrity Procedia 00 (2019) 000 – 000

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determined the fracture rate of steels used for manufacturing high-pressure vessels. This comparison shows the effectiveness of the proposed concept.

Fig. 8. Model of the physicochemical situation at the crack tip under the influence of the aggressive environment.

Fig. 9. Equipment for evaluation of the material fatigue fracture characteristics, considering the parameters of electrochemical processes in the process zone: a is a scheme of the microelectrode gauges placing in a specimen for local electrochemical measurements; b is a general view of the equipment.

Fig. 10. Fatigue crack growth rate diagram ( v – K -diagrams) for pressure vessels metal: 1 , 2 is according to ASTM Test Method; 3 , 4 is according to Bamford (1979) (a generalization of different experimental data); 5 is a basic diagram plotted according to the proposed concept.