PSI - Issue 38

Alexander Erbe et al. / Procedia Structural Integrity 38 (2022) 192–201 Author name / Structural Integrity Procedia 00 (2021) 000 – 000

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Figure 5: Comparison of load drop trends for axis A and B for different axis ratios at one load level  ε eq,DP and T = 400 °C.

Figure 6: lifetime curves of experimental results; left side normalized Δε eq,design versus normalized N i5% ; right side normalized Δ ε eq,HS versus normalized N i5%

As outlined before, even if the design point is used for initially designing the tests in terms of von Mises equivalent strain, the design point does not represent the location at which the maximum von Mises strain range is produced, Figure 3, right. With the use of the FEM calculation this maximum occurring von Mises strain (HS) is identified as well and used to assess the various axis ratios once again, Figure 6, right. Now, the axis ratio of = 0 is in good accordance with the uniaxial reference line. Starting from this, a relative lifetime increase representing by a curve offset can be concluded in the order of = -0.5, = 1, = -1. With regard to the design and the assessment of complex structures and loading configurations, the results indicate a positive statement, that the uniaxial case