A team from the Department of Energy’s Oak Ridge National Laboratory has worked with industry partners to use neutrons to probe a running engine at ORNL’s Spallation Neutron Source (earlier post), giving them the opportunity to test an aluminum-cerium alloy under operating conditions. The feat was a first for the Spallation Neutron Source, said Ke An, lead instrument scientist for the facility’s VULCAN instrument. “This was the first time an internal combustion engine has been run on our diffractometer, and, as far as we know, on any other,” he stated.
The unique properties of neutrons allow them to penetrate materials in a nondestructive fashion, revealing fundamental details about a material’s atomic structure. VULCAN uses neutrons to measure strain and stress on large industrial samples, which made it ideal for evaluating a cylinder head cast from an aluminum-cerium alloy ORNL developed in partnership with Eck Industries.
ORNL materials scientist Orlando Rios, who has been working through the Critical Materials Institute to explore the use of cerium as a strengthening agent for aluminum alloys, led the experiment. The experiment confirmed that the alloy outperforms other aluminum alloys at elevated temperatures, Rios said.
The automotive industry is currently interested in alloys that can hold up to high-heat demands of new, energy-efficient technologies. Our aluminum-cerium composition shows exceptional stability at temperatures above 500 degrees Celsius [932 degrees Fahrenheit], which is unheard of for aluminum alloys.—Orlando Rios
Lt. Eric Stromme, a Navy Tours with Industry Fellow who assisted on the project, added that with an aluminum alloy stable at high temperatures, engines could run hotter, and components could be made lighter, boosting efficiency and fuel economy.
Aided by colleagues at ORNL’s Manufacturing Demonstration Facility and the National Transportation Research Center, Rios’ team cast the Al-Ce cylinder head using 3-D–printed sand molds and retrofitted the component to a prototype engine designed specifically for VULCAN.
Over the three-day experiment—with the engine stopping and restarting via a remote ignition from VULCAN’s control room——neutron diffraction allowed the researchers to “see” the high-temperature stability of Al-Ce during the engine’s operating regime.
Materials experience complex forces and extreme temperatures during internal combustion, so the researchers wanted to measure material performance during actual operating conditions.
This research was sponsored by the DOE Office of Energy Efficiency and Renewable Energy through the Critical Materials Institute, a DOE Energy Innovation Hub, with additional funding from the DOE Office of Science. Partners include Ames National Laboratory, ORNL, Lawrence Livermore National Laboratory, Idaho National Laboratory, and Eck Industries. The Materials Science and Technology Division at ORNL led the experiment in collaboration with the Manufacturing Demonstration Facility, National Transportation Research Center, and the VULCAN instrument team.
The Spallation Neutron Source is a DOE Office of Science User Facility. UT-Battelle manages ORNL for the DOE Office of Science. The single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time.
The Manufacturing Demonstration Facility and the National Transportation Research Center are DOE EERE User Facilities supported by EERE’s Advanced Manufacturing Office and Vehicle Technologies Office, respectively.
The Critical Materials Institute is a Department of Energy Innovation Hub operated by Ames Laboratory for DOE and supported by EERE’s Advanced Manufacturing Office. CMI seeks to assure supply chains of rare earth elements and other materials critical to clean energy technologies—enabling innovation in US manufacturing and enhancing US energy security.