Jaime Marian: Then and now / 2012 Early Career Award winner

WHAT DID THE 2012 EARLY CAREER AWARD ALLOW YOU TO DO?

For a young engineering student widely interested in science, fusion energy research held an irresistible allure. Could we harness the energy from the sun in a controlled way here on Earth? That goal requires combining quantum mechanics, hydrodynamics, materials science, electromagnetism, and all kinds of engineering. It sounded like the great scientific and technical challenge of a generation. And more. Fusion energy also addresses societal challenges. We work towards a carbon-free source of energy, abundant fuel for everyone, energy independence, and geopolitical stability.

Through the advice and guidance of mentors and friends, I ended up in the stimulating world of fusion materials. Theory, modeling, and simulations research was a natural path for someone eager to make contributions to materials development. The Early Career Research Project award allowed me to concentrate my efforts on studying irradiation in materials. How does irradiation change materials’ properties? How do these changes impact fusion reactor design and operation?

For example, my colleagues and I found the mechanism by which irradiated materials deform. This way of deforming is harmful because it makes the materials susceptible to failing much sooner than if they had not been irradiated. 

Another example of how irradiation changes materials is by making some chemical elements mutate into completely different ones. This change means that in a fusion reactor, you end up with a completely different material after some time. The problem is that these new elements combine in ways that also make the material easier to fail by fracture.

Another crucial aspect of fusion materials is their ability to trap hydrogen isotopes (the main ‘fuel’ of fusion). This process must be closely monitored to avoid the accumulation of toxic elements during operation. Our simulations revealed how these isotopes are captured in small gas bubbles. We quantified how, when, and how much is trapped internally as the reactor is in operation.

The Award also allowed me to establish myself as a scientist working on the frontiers of science and engineering. Just as importantly, it helped me become part of a community of researchers. This community works at national and international levels to solve a global grand challenge. As a professor, I get great satisfaction from being now able to transmit the knowledge that I gained working under the support of the Department of Energy Early Career award to the next generation of scientists and engineers. My career allows me to close the circle that started with me as a student becoming captivated by the promise of the ultimate source of clean and abundant energy.

ABOUT:

Jaime Marian is a professor in the Department of Materials Science and Engineering at the University of California, Los Angeles.

SUPPORTING THE DOE SC MISSION:

The Early Career Research Program provides financial support that is foundational to early career investigators, enabling them to define and direct independent research in areas important to DOE missions. The development of outstanding scientists and research leaders is of paramount importance to the Department of Energy Office of Science. By investing in the next generation of researchers, the Office of Science champions lifelong careers in discovery science.

 For more information, please go to the Early Career Research Program.

THE 2012 PROJECT ABSTRACT: 

Computational Modeling and Design of Radiation‐Tolerant Materials for Fusion

In nuclear fusion environments, materials are subjected to extreme conditions of radiation, temperature, and mechanical load. Over time, this results in performance degradation to extents that may render these materials unsuitable for the purpose for which they were originally designed.

The objectives of this research are to use theory, modeling, and simulation to predict materials performance over the expected lifetime of fusion devices. This will result in an economical yet scientifically based way to test different design alternatives, suggest component improvements, and provide fusion plant design optimization. This research will advance the current state of the art in computational modeling one step further toward a ‘materials‐by‐design' strategy for energy applications.

RESOURCES:

J Marian, CS Becquart, C Domain, SL Dudarev, MR Gilbert, RJ Kurtz, DR Mason, K Nordlund, AE Sand, LL Snead, T Suzudo, and BD Wirth, "Recent advances in modeling and simulation of the exposure and response of tungsten to fusion energy conditions." Nuclear Fusion 57, 092008 (2017). [DOI:10.1088/1741-4326/aa5e8d]

CH Huang, L Gharaee, Y Zhao, P Erhart, and J Marian, “Mechanism of nucleation and incipient growth of Re clusters in irradiated W-Re alloys from kinetic Monte Carlo simulations.” Physical Review B 96, 094108 (2017). [DOI: 10.1103/PhysRevB.96.094108]

A Arsenlis, M Rhee, G Hommes, R Cook, and J Marian, "A dislocation dynamics study of the transition from homogeneous to heterogeneous deformation in irradiated body-centered cubic iron." Acta Materialia 60, 3748 (2012). [DOI: 10.1016/j.actamat.2012.03.041]

Additional profiles of the Early Career Research Program award recipients can be found at /science/listings/early-career-program. 

The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit the Office of Science website.