Scientists from MEPhI have proposed a new method of joining the materials of the plasma-faced wall of a thermonuclear reactor. For this purpose, the innovative TiZr4Be solder was developed for joining tungsten to steel.

DEMO reactor complex project

The Demonstration Fusion Reactor (DEMO) will be the next step in preparing for the use of fusion energy on an industrial scale. In the ITER currently under construction near Marseille (France) the walls are based on chromium-zirconium bronze with soldered "tiles" of tungsten or beryllium. In DEMO, where the loads on the reactor walls will be much more powerful, heat-resistant steel will be needed. However, among others, a serious problem remains - it is necessary to create a heat-resistant one-piece connection of steel and tungsten.

For this purpose, it is necessary not only to obtain a new solder alloy from low-activated elements and work out the modes of soldering tungsten with steel, but also to understand the areas of application of such soldered joints in the environment of hydrogen isotopes - the fuel of thermonuclear reactors. This was done by a group of scientists at MEPhI: joint efforts of the departments of physical problems of materials science and plasma physics developed the TiZr4Be solder for soldering tungsten with steel EK-181 and determined the conditions for the use of such solder joints in a hydrogen environment.

The results of the work were published in the highly-rated scientific journal Journal of Nuclear Materials.