3D printing goes nuclear with molybdenum

Oak Ridge National Laboratory and BWX Technologies have recently developed a new method to manufacture and qualify parts for high-temperature nuclear reactor applications by using 3D printing.

BWXT, a Virginia-based nuclear fuel and component supplier, successfully 3D-printed core structural parts used in nuclear propulsion designs, something that was previously considered impossible with conventional manufacturing methods.

Collaborating with Oak Ridge researchers, BWXT used an electron beam melting system to print intricate parts from molybdenum, a refractory metal with high resistance to heat and wear.

Each one millimeter- (0.39 inches) thick layer was digitally captured during the printing process, which was then used to qualify the integrity of the components.

"Projects like these allow us to bring to bear our core expertise in the science of materials processing to deliver solutions specific to the demanding nature of nuclear energy applications," said Michael Kirka, a materials scientist from Oak Ridge National Labs.

Refractory materials such as molybdenum are extremely difficult to fabricate given the extreme environments needed to create a component using the sturdy material.

Utilizing facilities at Oak Ridge, a U.S. Department of Energy-sponsored laboratory, the team was able to design complex geometries that would otherwise have been practically impossible to manufacture using typical processes.

The successful demonstration was the result of a nearly $10 million cost-share award given by the Department of Energy Office of Nuclear Energy in 2018 to leverage innovations in additive manufacturing and data science.

The production of component-level qualified nuclear materials, like molybdenum, now opens the door for new advanced reactor designs that could potentially yield higher efficiencies at a fraction of the cost.

"This is a great example of how a cost-share program can provide great benefits for the nuclear industry," said Joe Miller, president of BWX Technologies. "We were able to utilize BWXT's design, data science, and advanced manufacturing expertise along with ORNL's facilities and subject matter experts to deliver a first-of-a-kind manufacturing process for extreme-temperature capable materials."

Once fully explored and tested, BWXT's latest process is expected to be applied to the commercial market, which should greatly reduce the overall development and fabrication costs of future nuclear reactors.