In the quest for sustainable energy, nuclear fusion stands out as a beacon of potential, promising to deliver vast amounts of energy with minimal environmental impact. However, the road to operational fusion reactors is fraught with challenges, particularly when it comes to the materials used in critical components like the divertor target. A recent study led by Triestino Minniti from the Department of Physics at the University of Rome Tor Vergata sheds light on these challenges, utilizing advanced techniques to assess the structural integrity of divertor mock-ups.
The divertor target plays a vital role in managing heat and exhaust particles in fusion reactors, especially in the upcoming European demonstration reactor (EU-DEMO). This reactor is expected to experience extreme heat fluxes, peaking at an astonishing 40 megawatts per square meter during transient events. Ensuring the reliability and longevity of divertor targets under such conditions is paramount. Minniti emphasizes this point, stating, “The mechanical stability of the materials used in divertor targets is not just a technical requirement; it’s a prerequisite for the success of fusion energy.”
The research employs Bragg edge neutron imaging—a cutting-edge non-destructive evaluation technique—to map residual strains in divertor materials like tungsten and CuCrZr before and after they undergo high-heat flux testing. The study addresses a significant gap in current understanding: the uncertainty surrounding the stress states of divertor components due to fabrication processes and extreme operational loads. By providing a clearer picture of these residual stresses, the work sets the stage for improving the design and material selection for future fusion reactors.
Neutron tomography measurements further enhance the ability to evaluate the structural integrity of these components. This non-invasive approach not only preserves the integrity of the samples but also provides valuable data that can inform future designs. “Our findings could lead to more reliable and efficient materials for fusion reactors, ultimately accelerating the timeline for commercial fusion energy,” Minniti notes.
The implications of this research extend beyond the laboratory. As the energy sector increasingly seeks solutions to meet growing global demands while addressing climate change, the advancement of nuclear fusion technology could play a pivotal role. By ensuring the reliability of divertor targets, this research supports the broader goal of making fusion a viable energy source, potentially transforming how we think about power generation in the coming decades.
Published in the journal ‘Nuclear Fusion,’ this study represents a significant step forward in the ongoing development of fusion technology. As researchers continue to refine materials and techniques, the dream of a sustainable and virtually limitless energy source moves closer to reality.
