ARGONNE, Ill., Aug. 6 (UPI) -- U.S. government scientists say they've discovered networks of metal nanoparticles are the cause of alloy corrosion.
Researchers at the U.S. Department of Energy's Argonne National Laboratory said oxide scales developing on the outer surface of alloys at high temperatures usually create a protective barrier that keeps destructive carbon-bearing molecules from slipping into the alloy.
The researchers said it has been believed carbon-containing molecules escaped into cracks or pores in the oxide scales causing the corrosion. But using three techniques -- nanobeam X-ray analysis, magnetic force microscopy and electron scanning microscopy -- Argonne scientists Ken Natesan, Zuotao Zeng, Seth Darling and Zhonghou Cai discovered networks of iron and nickel nanoparticles embedded within the oxide scales were the culprits.
Based on the study, researchers developed laboratory size batches of materials that exhibit as much as 10 times longer life than commercial alloys. The scientists said their findings might be of interest in other research areas such as alloy development and surface coatings for high-temperature fuel cell applications.
A paper based on the work appeared in the journal Nature Materials.
