PSI - Issue 2_B

B. Fedelich et al. / Procedia Structural Integrity 2 (2016) 2190–2197 Author name / Structural Integrity Procedia 00 (2016) 000–000

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The formula (10) has been evaluated for the alloy EN GJS XSiMo 4.05. For this purpose, the parameters cyc  and ' n of the cyclic Ramberg-Osgood model have been determined in the temperature interval 300-700°C. Fig. 5 shows the correlation between HCF  and the fatigue life reduction factor TMF HCF TMF N N  . Note that the parameter HCF  is related to the maximal value of HCF CTOD  during a TMF+HCF block by equ. (7). The denominations of the tests are the same as in Fig. 3. Apart from the large scatter, a consistent trend can be observed with no pronounced systematic deviations.

Fig. 5. Correlation between HCF  and

TMF HCF TMF N N  .

Finally, the parameters 0 f a a needed to evaluate equ. (9) have been determined by fitting the available experimental data. Fig. 6 shows the agreement between the calculated and the experimental fatigue life reduction factors TMF HCF TMF N N  . Despite the simplicity of the model and the fact that only two parameters were fitted, most data points lay within a scatter band of width corresponding to a deviation of a factor 2. 0 th CTOD a  and

Fig. 6. Predicted lifetime reduction

TMF HCF TMF N N  (SIM) versus experimental lifetime reduction

TMF HCF TMF N N  (EXP).