In the relentless pursuit of sustainable energy, the quest for materials that can withstand the extreme conditions of nuclear fusion reactors has led to a significant breakthrough. Researchers, led by Yue Yuan from the School of Physics at Beihang University in Beijing, have discovered that lanthanum-doped tungsten (WL10) exhibits remarkable resistance to cavitation, a critical issue for plasma-facing materials in fusion devices like ITER and DEMO.
Cavitation, the formation of voids and bubbles in materials subjected to intense heat and pressure, can severely degrade the performance and lifespan of plasma-facing components. Previous studies had shown that WL10 could suppress cavitation under a single pulsed heat load. However, the real challenge lies in its behavior under multiple melt exposures, mimicking the harsh, repetitive conditions in a fusion reactor.
The research, conducted in both the high heat flux facility GLADIS and the tokamak ASDEX Upgrade (AUG), subjected pure tungsten and WL10 to intense heat loads. The results were striking. While pure tungsten samples showed pronounced cavitation with numerous spherical voids, WL10 developed an undulating surface morphology with a dense, void-free resolidified layer. This layer remained intact even after the lanthanum oxide had vaporized from the surface, indicating a sustained suppression of cavitation.
“The undulating surface morphology is key,” Yuan explains. “It exposes deeper material regions rich in lanthanum oxide, which continuously prevents cavitation during subsequent melting cycles.”
This discovery has profound implications for the energy sector. Fusion power, with its promise of nearly limitless, clean energy, has long been hampered by material challenges. The ability to suppress cavitation in plasma-facing materials could significantly extend the lifespan of fusion reactor components, making fusion power a more viable and economical option.
Moreover, the research revealed that deuterium retention, a critical factor in fusion reactor performance, was significantly reduced in WL10 samples. This finding could lead to safer and more efficient fusion reactors, further accelerating the commercialization of fusion power.
The study, published in the journal Nuclear Fusion, translates to English as “Nuclear Fusion,” underscores the potential of lanthanum-doped tungsten in advancing fusion technology. As the world continues to seek sustainable energy solutions, innovations like this bring us one step closer to harnessing the power of the stars.
