PSI - Issue 23

Yoshitaka Umeno et al. / Procedia Structural Integrity 23 (2019) 348–353 Author n me / Structur l Integrity Procedia 00 (2019) 000 – 00

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Fig. 6: Stress-strain relationships obtained with various number-average molar masses. Thermal fluctuation in curves is smoothed by the Bezier approximation for clarity.

4. Conclusion

In the present study, we performed CGMD simulations of PC to acquire understanding of deformation and fracture behaviors. We calculated yield stress as a function of strain rate by tensile simulations of four types of loading; uniaxial stress, biaxial stress, uniaxial strain and isotropic stress. We obtained two master curves of yield stress-strain rate relation; one for the former two loading types and the other for the latter two. The curves can be used for various temperatures using the WLF equation with proper shift factors. We also found the effect of molar mass on stress-strain curves; i.e. the larger the molar mass is, the larger stress can be attained after yielding, suggesting brittle-ductile transition with increasing molar mass, which is indicative of the effect of entanglement of molecular chains.

Acknowledgements

Authors acknowledge financial support by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan).

References

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