Computational discovery of complex alloys could speed the way to green aviation

Date:
October 29, 2021
Source:
DOE/Ames Laboratory
Summary:
Experts have identified the way to tune the strength and ductility
of a class of materials called high-entropy alloys. The discovery
may help power-generation and aviation industry develop more
efficient engines.



FULL STORY ========================================================================== Computational materials science experts at the U.S. Department of Energy's
Ames Laboratory and their collaborators have identified the source of
and the way to tune the strength and ductility of a class of materials
called high-entropy alloys. The discovery may help power-generation
and aviation industry develop more efficient engines, reducing fuel
consumption and carbon emissions.


========================================================================== High-entropy alloys are composed from four or more different elements,
and often have many desirable properties -- they are lightweight, strong, ductile, corrosion resistant and ideal for energy-generation applications
in extreme environments, like aviation. But, because the elements
that make up an alloy can vary, as well as their relative proportions, experimentally testing the sheer number of possible combinations and
their properties is difficult and time-consuming.

The Ames Laboratory-led team used a quantum-mechanical modelling
method to computationally discover and predict the atomic structure
of a particularly promising HEA system, FexMn80?xCo10Cr10, and how transformations and defects in that structure result in a stronger,
more ductile material.

"When we can pinpoint these transformations and the effect they have
on a material's properties, we can predict the strength of it, and
we can deliberately design strength and ductility into these very
complex alloys," said Ames Laboratory scientist Duane Johnson. These predictions were then confirmed experimentally, studying single-crystal
samples with advanced electron microscopy, including selective-area and electron-backscattered diffraction. Notably, the method is applicable
to any multi-element complex alloy.

Theory-guided computational design, Johnson said, holds great promise
for optimizing the performance of these materials, making them stronger,
more ductile, and in many cases, less expensive. These performance
improvements could have big implications for applications in extreme environments, like turbine engines for power-generation or aviation,
which work more efficiently at higher temperatures.

"Using this predictive method, we've been able to speed up our alloy development timeline by more than 50%, and demonstrate 10-20% higher operational temperatures," said Johnson. In the case of aviation, he said,
this could translate into hundreds of millions of dollars in cost savings,
and a significant reduction in greenhouse emissions.

========================================================================== Story Source: Materials provided by DOE/Ames_Laboratory. Note: Content
may be edited for style and length.


========================================================================== Journal Reference:
1. P. Singh, S. Picak, A. Sharma, Y. I. Chumlyakov, R. Arroyave,
I.

Karaman, Duane D. Johnson. Martensitic Transformation in FexMn80-
xCo10Cr10 High-Entropy Alloy. Physical Review Letters, 2021; 127
(11) DOI: 10.1103/PhysRevLett.127.115704 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/10/211029103118.htm

--- up 8 weeks, 1 day, 8 hours, 25 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)