Novel method for determination of tritium depth profiles in metallic samples

Abstract

Novel method for determining the depth profile of tritium in metallic samples has been demonstrated. Tritium accumulation in the fusion reactor materials is considered as a radiological issue due to its radioactivity. Therefore, tritium behavior prediction and estimation of its overall retention in fusion devices is of high importance. Proposed method in this study allows to measure depth profile of tritium in the metallic samples after exposure to tritium containing plasma, tritium gas or after irradiation with neutrons resulting in the tritium formation. In the method, successive layers of metal are removed using appropriate etching agent in the controlled regime and amount of evolved gases measured by the means of chromatography (gas composition and release rate) and proportional gas flow detector (tritium). Results on tritium profile in neutron irradiated, plasma exposed and tritium gas loaded beryllium have been reported and possible applications of the method for other metallic samples have been tested within this research.

Tritium in plasma-facing components of JET with the ITER-Like-Wall

“…Chemical and electrochemical etching can be applied to the metallic samples and gives information both on total tritium amount and its depth profile [34] 2. Experimental…”

“…Beryllium can be etched chemically in acid solutions, whereas for tungsten and Inconel electrochemistry must be applied due either to their low reactivity with chemical etchants or formation of complex mixtures of the reaction products. Detailed description of the methods for Be and W is given in [34]. In case of Be coated Inconel combination of chemical (beryllium) and electrochemical (Inconel) etching has been applied that gives opportunity to measure separately tritium accumulated in the coating and substrate.…”

Fuel desorption from JET-ILW materials: assessment of analytical approach and identification of sources of uncertainty and discrepancy

“…Inter-shot analysis TEXTOR [32] [42] NRA for H p( 15 N,α) 12 Both 12 C-t reactions tried on JET materials [57], while the d-t reaction was used on TFTR tiles [58] (Continued.) T analysis by LSC [76] are difficult to study using wall probes because the shortest interval between the probe exposure and D analysis amounts to several hours, i.e. the time necessary for probe withdrawal, venting of the probe system, retrieval of material and transfer to the surface analysis station.…”

“…Dissolution measurements were performed at the UoL (Facility C). Details of the experimental setup can be found in [91]. In this technique, investigated samples are etched chemically (Be samples, using sulfuric acid) or electrochemically (W samples, using 30% KOH solution) such that T is released simultaneously with the dissolution of the sample.…”

Critical Evaluation of the Methods for the Characterization of the Degree of Sulfonation for Electron Beam Irradiated and Non-Irradiated Sulfonated Poly(ether ether ketone) Membranes

“…As the performance of PEMs is highly dependent on the sulfonation degree, a reliable and fast method for the determination of DS is required [14,[22][23][24]. Due to its good radiation stability, SPEEK can also be used in radiation environments, such as nuclear facilities, space applications and proton exchange membrane-based enrichment of the hydrogen radioactive isotope, tritium [25,26]. Insufficient research has been performed to determine the effects of ionizing radiation on the DS, as well as how electron beam radiation affects the structure of the membrane, which affects the determination of DS.…”