Characterization of mechanical strain induced by lead-bismuth eutectic (LBE) freezing in stainless steel cup

Abstract

Lead-bismuth eutectic (LBE) is a candidate liquid metal coolant for a fast reactor, especially accelerator driven system (ADS). Freeze sealed valve is a candidate design to be possible to add passive safety to the reactor. On the other hand, since LBE is known that it causes expansion after its solidification, quantitative evaluation of the stress to the pipe produced by the LBE expansion should be considered. Many researchers produced related data for the expansion, however, evaluations of the strain by LBE expansion was barely reported. Therefore, the strain measurement using a stainless steel cup and the stress evaluation was performed together with visual observation using an optical microscopy. The results indicated keeping above room temperature (RT) was a significantly effective way to reduce the strain to the pipe.

Aluminum Oxide Ceramic Coatings on 316l Austenitic Steel Obtained by Plasma Electrolysis Oxidation Using a Pulsed Unipolar Power Supply

“…AISI 316L steel becomes a good choice of structural material for the fusion reactor in the future, owing to its excellent processability and high temperature stability, but the structural pipe fittings achieved by 316L stainless steel are easily corroded by a large amount of highly permeable and corrosive tritium in the operating environment of fusion reactor [22]. The world-wide acknowledged solution is to prepare alumina ceramic coatings on the inner surface of stainless-steel pipes, which cannot only guarantee the structure property of pipe systems, but also protect the pipes from the permeation and corrosion of tritium [12].Austenitic 316L steel has already been extensively used as a nuclear structural material and is among the materials selected for nuclear systems with Heavy Liquid Metals (HLM) [5,23] as lead or Lead Bismuth Eutectic (LBE) [24]. The use of HLM raises problems with the compatibility of materials in terms of corrosion and mechanical strength [25,26].…”

“…Austenitic 316L steel has already been extensively used as a nuclear structural material and is among the materials selected for nuclear systems with Heavy Liquid Metals (HLM) [5,23] as lead or Lead Bismuth Eutectic (LBE) [24]. The use of HLM raises problems with the compatibility of materials in terms of corrosion and mechanical strength [25,26].…”