3D printed steel capsules withstand nuclear reactor testing

The Department of Energy’s Oak Ridge National Laboratory has set new milestones in nuclear components innovation and successfully tested two 3D printed stainless steel experimental capsules in the lab’s High Flux Isotope Reactor (HFIR).

This achievement is an important step in demonstrating that the added components can meet the strict safety standards required for nuclear applications.

These capsules are used to hold sample materials during irradiation experiments, allowing researchers to test how these materials react in a nuclear reactor. Capsules provide a barrier to experimental pressure and containment. This is an important safety feature.

The ORNL team 3D printed 316H stainless steel capsules using a laser powder bed system at the lab’s manufacturing demonstration facility (MDF). This type of steel has been evaluated for its safe and durable use in reactor environments, as it offers high temperature strength, corrosion and radiation resistance, proven nuclear environments and weldability, and provides a nuclear-grade performance.

The team then assembled and qualified the capsules and inserted into the HFIR by the irradiation engineering group at ORNL. The capsules were irradiated to the reactor for a month and removed completely intact. This demonstration sets stages for future nuclear component designs produced using additive manufacturing.

“As we demonstrate the reliability of these printed components, we are considering a future in which additive manufacturing could become a standard practice in the production of other critical reactor components,” said Ryan Dehoff, MDF Director, ORNL.

HFIR offers one of the world’s highest neutron flux environments, allowing researchers to qualify by testing fuels and materials under conditions such as nuclear reactors. Manufacturing and qualifying experimental capsules for irradiating fuel and materials samples is a costly and time-consuming process and requires custom materials and design.

The manufacture of additives, or 3D printing, can streamline the development of experimental capsules, significantly reduce the costs and time associated with the production of these components, and ultimately promote the innovation of nuclear science and technology.

“The nuclear materials and fuel research community is being asked to qualify for advanced reactor technology to withstand extremely harsh conditions. The summed products will expand my group’s toolset to develop innovative experiments to support this critical need.”

This work was sponsored by the DOE Office of Nuclear Energy’s Advanced Materials and Manufacturing Technologies program. HFIR is the DOE office of science user facilities. Supported by DOE’s Advanced Materials and Manufacturing Technologies Office, MDF is a national consortium of collaborators working with ORNL to innovate, stimulate and catalyze US manufacturing transformation.

UT-Battelle manages the ORNL of the Department of Energy’s Science Bureau, the largest supporter of basic research in the US physical sciences. The Science Bureau is working to address some of the most pressing challenges of our time.