PSI - Issue 5

Kulbir Singh et al. / Procedia Structural Integrity 5 (2017) 294–301 Author name / Structural Integrity Procedia 00 (2017) 000 – 000

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Fig. 1. Comparison of numerically predicted critical shear stress on active slip system with experimental results..

5. Results and discussion Results of non-irradiated and irradiated case in terms of total dislocation density ( ρ tot ) on primary slip system for various temperature w.r.t. strain on primary slip system ( ɛ pss ) are shown in Fig. 2. The value of ρ tot increase with an increase in temperature and applied strain. Effect of irradiation (presence of interstitial loops) increases the total dislocation density value and also shifts the total dislocation density evolution with strain from linear to non-linear as compared to non-irradiated case.

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Fig. 2. Total dislocation density vs. strain on primary slip system (a) Non-irradiated case; (b) Irradiated case.

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Fig. 3. Temperature dependence of various shear stresses at 5% strain (a) Non-irradiated case; (b) Irradiated case.

The temperature dependent evolution of shear stresses, τ c , τ eff and τ RSS at 5 % plastic strain (on the primary slip system) are shown in Fig. 3. It should be noted that the τ LT contribution (see section 2) is mostly negligible at low temperature: it starts contributing when l s reaches it critical value l min and this happens at higher temperature (mainly