PSI - Issue 60

Brahmadathan V B et al. / Procedia Structural Integrity 60 (2024) 214–221 Brahmadathan V B, C Lakshmana Rao/ Structural Integrity Procedia 00 (2019) 000 – 000

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As the strain rate increases, for example, at a strain rate of 10 6 s -1 , the effect of the distribution becomes less significant. At a higher strain rate, inertia becomes more critical. The nature of the stress-stain curve also depends on the crack-growth law (equation 10) parameters α and ϒ .

Figure 6. Stress strain response at ̇ =10 3 −1

Figure 7. TSI evolution at ̇ =10 3 −1

Figure 8. Stress strain response at ̇ =10 6 −1

Figure 9. TSI evolution at ̇ =10 6 −1

The current model also captures the strain rate sensitivity on the compressive strength (Figure 10). The transition strain rate is found to be 1000 s -1 in this study. The results are compared with the strain rate sensitivity relations obtained from Lankford.

0 1000 2000 3000 4000 5000 6000 7000 8000 9000

Normal

Weibull (skew parameter=1.2) Weibull (skew parameter=2.4) Exponential

Compressive strength (MPa)

-4

-2

0

2

4

6

8

Log of strain rate

Figure 10. Compressive strength vs log of strain rate for different PDF