PSI - Issue 14

T. Narayana Murty et al. / Procedia Structural Integrity 14 (2019) 664–667 Narayana Murty et al/ Structural Integrity Procedia 00 (2018) 000 – 000

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Fig. 2. Effect of indentation load on hydride orientation near punch marks.

4. Conclusions

Indentation was made on the radial- circumferential plane of Zr-2.5% Nb pressure tube, thereafter it was charged with 50 wppm hydrogen. Punching load was varied to investigate its effect on radial hydride formation. The pattern of hydride formation is same for every load. But, fraction of radial hydride formation was observed to increase with increase in punch load. For the loads having value more than 400 N, radial hydrides were observed to be formed through thickness. Similar kind of experiments have to be performed on axial- circumferential plane along with a detailed stress analysis to understand the hydride orientation and its effect on the integrity of the pressure tube. Acknowledgements

Constant encouragement and support provided by Dr. Madangopal K., AD Materials Group is acknowledged.

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