Laser dissolution of refractory material for techniques need liquid sampling

Post irradiation examination of nuclear fuel and associated material is important for various reasons. Commonly used techniques for such characterization are destructive in nature and demands liquid sampling. Complete dissolution of refractory materials such as B₄C used as control rod and metal alloy fuel containing Zr is challenging task in nuclear industry. Among the different routes, laser dissolution is a favoured method because of its inherent advantages over others conventional methods such as (i) no ingress of extra impurity, (ii) stoichiometric transfer of material with optimized laser parameters, (iii) efficient dissolution due to formation of finer particles in the ablation process, (iv) can be employed at remote location and hence dissolution of radioactive samples is not an issue. In the present study, three U-Zr metal alloy samples (U-2 wt.% Zr, U-5 wt.%Zr, 100 wt.% Zr) are dissolved separately using Nd:YAG laser. Sample in the form of pellet is prepared by Arc melting. Each target pellet was ablated with 1064 nm Nd:YAG laser of energy 70 mJ and frequency 10 Hz for about 8 hrs