Future fusion goals: US’ DREAM TEAM to 3D-print tungsten for nuclear reactors

Iowa University, in collaboration with the Department of Energy (DOE), has begun work on the DREAM TEAM project, which will use 3D printing technology to make heat-resistant shields with tungsten for nuclear reactors.

DREAM TEAM stands for Developing a Robust Ecosystem for Additive Manufacturing of Tungsten for Extreme Applications and Management.

Increasing concerns about carbon emissions and ambitions to reach net zero emissions in the coming decades have put the spotlight on nuclear power as a potential source of carbon-free energy.

Power derived from nuclear fission is one of the largest sources of clean power in the US. The US Energy Information Administration estimates show that nuclear fission contributes 19 percent to the electricity supply. In comparison, wind turbines contribute only 10 percent of the energy mix.

With an eye on further developing nuclear fusion technology, the DOE has assembled the DREAM TEAM.

What is the DREAM TEAM?

Led by Sougata Roy, an assistant professor of mechanical engineering at Iowa University, the DREAM TEAM consists of Yachao Wang, also an assistant professor of mechanical engineering at the University of North Dakota, and researchers from DOE’s three national laboratories, namely the Ames National Laboratory, Argonne National Laboratory and Oak Ridge National Laboratory.

Roy brings his expertise in additive manufacturing, or 3D printing , as it is popularly known, to the team. He will use it to construct heat shields and components for use inside nuclear reactors.

Although his previous work is unrelated to clean energy, Roy is keen to work in the area. “One of the major things that excites me about this project is working with nuclear energy. This emission-free electricity is important for the future,” said Roy in a statement.

What will DREAM TEAM do with tungsten?

The DREAM TEAM project is part of the DOE’s Established Program to Stimulate Competitive Research (EPSCoR), designed to build US energy-related capabilities.

At DREAM TEAM, researchers will work with tungsten, a material of choice for the inner walls of nuclear reactors because it has a high melting temperature and can withstand high temperatures. It is also a preferred material for the walls of fusion reactors because it resists erosion when bombarded with neutron radiation and does not retain high levels of radioactive tritium.

The problem with using tungsten is that it is hard but brittle and difficult to incorporate into manufacturing processes.

The team led by Roy will instead use a laser powder-blown directed energy deposition technique to 3D print tungsten. In this unconventional approach to working with tungsten, the research team will use a laser in oxygen-controlled conditions and print tungsten metal layer by layer onto nuclear reactor walls.

A $1 million grant for the project will also enable the team to procure equipment to analyze and characterize the mechanical properties of the 3D-printed samples. As a researcher, Roy is keen on physics-based modeling and computational simulations, which are needed before 3D printing takes place.

The researchers will build theories based on their experimental findings using machine learning and artificial intelligence. But tungsten is just the beginning.

“We’ll start with pure tungsten,” Roy added in a press release . “Eventually we’ll develop new alloys to resolve this cracking challenge.”