Materials scientists now have the ability to leverage knowledge from a widely found mineral and established statistics on earthquakes and avalanches to assess how challenging environmental factors could affect the deterioration and malfunction of materials used in advanced solar panels, geological carbon capture, and infrastructure like buildings, roads, and bridges.
Materials scientists now have the ability to leverage knowledge from a widely found mineral and established statistics on earthquakes and avalanches to assess how challenging environmental factors could affect the deterioration and malfunction of materials used in advanced solar panels, geological carbon capture, and infrastructure like buildings, roads, and bridges.
A recent study, spearheaded by the University of Illinois Urbana-Champaign in partnership with Sandia National Laboratories and Bucknell University, reveals that the deformation resulting from stress applied to the surface of muscovite mica is influenced by the mineral’s surface condition and follows statistical patterns akin to those seen in earthquakes and avalanches.
The findings of this research are detailed in the journal Nature Communications.
In choosing materials for engineering projects, scientists are keen to understand how a material’s surface will behave in its intended environment. Similarly, geologists are interested in how chemical interactions between minerals and groundwater along fault lines could gradually weaken rocks, leading to sudden mechanical failures often referred to as chemomechanical weakening.
“While earlier efforts to quantify the impact of chemomechanical weakening on engineered materials relied on intricate molecular dynamics models that require considerable computational power, our research highlights the connection between lab experiments and real-world events like earthquakes,” stated graduate student Jordan Sickle, who collaborated closely with Illinois physics professor Karin Dahmen on the study.
“Muscovite was selected for this investigation primarily due to its exceptional flatness,” Dahmen noted. “Each of its layered flakes is extremely flat down to the atomic scale. This flatness makes the interaction between this material’s surface and its surroundings particularly significant.”
To assess chemomechanical weakening on muscovite surfaces, researchers from Sandia National Laboratories subjected samples to various chemical environments—dry, submerged in deionized water, and in salt solutions at pH levels of 9.8 and 12. During the experiment, a device called a nanoindenter pressed against the minerals’ surface and recorded any displacements or failures at regulated mechanical loads.
The findings indicated that muscovite can withstand greater deformation in dry conditions compared to wet conditions before failing. When failure occurred, all samples released their stored elastic energy. The study found that exposure to a basic solution at pH levels of 9.8 or 12 weakened the topmost layer of muscovite, reducing the energy it can store before failing, a trend observed in burst statistics.
“The outcomes of this study allow researchers to evaluate material failure more efficiently than traditional high-powered simulation models,” Sickle explained. “By demonstrating that we can achieve comparable results using established statistical models for earthquakes, researchers will be able to conduct material analysis at a higher throughput than previously achievable.”
This research is supported by the U.S. Department of Energy and Sandia National Laboratories.