Researchers from Sandia National Laboratories discovered that a 3D-printed superalloy can help power plants produce more electricity and less carbon as the world searches for ways to reduce greenhouse gas emissions.
Sandia scientists worked with Ames National Laboratory, Iowa State University, and Bruker Corp. to create a superalloy or high-performance metal alloy. This unusual composition makes it stronger than the state-of-the art materials used in gas turbine machines. The findings could have significant impacts in the energy and aerospace industries as well as in the automotive and automotive industries.
Andrew Kustas, Sandia scientist said, “We are showing that this material is capable of accessing previously unattainable combinations high strength low weight high-temperature resilience,” We believe that additive manufacturing is a key reason for our success.
The journal published the findings of the team. Applied Materials Today.
Material that resists heat is crucial for power plant turbines
According to the U.S. Energy Information Administration (USAEIA), about 80% electricity in the United States comes from either nuclear or fossil fuel power plants. Both types of power plants rely on heat to generate electricity. The temperature at which the turbines are heated can affect power plant efficiency. According to Sal Rodriguez, a Sandia nuclear engineer, turbines that can operate at higher temperatures will “convert more energy to electricity while reducing the amount heat released into the environment.”
Sandia’s experiments revealed that the superalloy (42% aluminum, 25% titan, 13% Niobium, 8% Zirconium and 4% Tantalum) was stronger at 800° Celsius (1,472° Fahrenheit). It was also stronger when brought back to room temperature.
Rodriguez said, “This is therefore a win for more economic energy and the environment.”
These findings are not limited to energy. Aerospace researchers are seeking lightweight materials that resist high heat. Nic Argibay, a scientist at Ames Lab, said that Sandia and Ames are working with industry to see how these alloys could be used in automotive manufacturing.
“Electronic structure theory, led by Ames Lab, was able to provide an explanation of the atomic origins these useful properties. We are now in process of optimizing the new class of alloys for manufacturing and scalability problems,” Argibay explained.
This research was funded by the Department of Energy and Sandia’s Laboratory Directed Research and Development Program.
Discovery highlights the changes in materials science
3D printing is also known as additive manufacturing. It is a flexible and efficient manufacturing process. Common printing techniques use a high-power laser to flash melt a material. This is usually a plastic or metal. As the molten material cools rapidly, the printer layers it and builds an object.
New research shows how this technology can be repurposed to make new materials. Sandia team members used the 3D printer to melt powdered metals quickly and then print a sample.
Sandia’s invention also marks a significant shift in alloy development, as no single metal is more than half of the material. Steel, on the other hand, is 98% iron and carbon combined with various other elements.
Kustas stated, “Iron and some pinch of carbon changed our world.” We have many examples of how two or more elements can be combined to make an engineering alloy. We are now able to combine four, five or more elements into one material. That’s when the material science and metallurgical perspectives really start to be interesting and challenging.
Cost and scaleability are the biggest challenges.
Moving forward, the team is interested in exploring whether advanced computer modeling techniques could help researchers discover more members of what could be a new class of high-performance, additive manufacturing-forward superalloys.
These are very complex mixtures,” stated Sandia scientist Michael Chandross. Chandross is an expert in computer-scale atomic modeling and was not involved in the study. All these metals interact at microscopic levels, even the atomic level. It’s those interactions which determine how strong, malleable, and what their melting points will be. Because it can calculate all this and allow us to predict how a new material will perform before it is manufactured, our model takes much of the guesswork out metallurgy.
Kustas stated that there are still challenges. One is that it may be difficult to make the superalloy in large quantities without microscopic cracks. This is a common challenge in additive manufacturing. The alloy’s materials are also expensive, he said. The alloy may not be suitable for consumer goods where cost is a major concern.
Kustas stated, “With all these caveats, this is scalable, and we can make bulk parts out of this, then it’s a big game changer.”
National Laboratories Sandia National is a multimission laboratory run by National Technology and Engineering Solutions of Sandia LLC. It is a wholly-owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy’s National Nuclear Security Administration. Sandia Labs is responsible for major research and development in nuclear deterrence and global security. Its main facilities are located in Albuquerque (New Mexico) and Livermore (California).
