Put steel under a powerful microscope, revealing its microstructure, and prepare to be surprised. Known for its strength, the metal will appear pitted and pocked. The pitting is cause for concern for industry because it can progress and lead to corrosion. But Carolyn Aita, Wisconsin Distinguished Professor of Engineering, can help. In her state-of-the-art lab at the College of Engineering and Applied Science, Aita has developed a host of coatings that heal shallow pits and fractures on almost any material. The coatings also prevent further degradation.
In sputter deposition, energetic ions formed from a vapor bombard the target, sending energetic atoms from it scattering like billiard balls in a game of pool. Those atoms then coat the substrate in ultra-thin layers.
In her current work, which is funded by a Rockwell Catalyst Grant from the UWM Research Foundation, Aita and four graduate students are creating new coatings that can withstand the corrosion that occurs in metals in an industrial setting.
“My coatings are designed to work in adverse environments, such as in salt spray, oil, high humidity,” says Aita. “We design them to address whatever causes damage to the substrate.”
Rockwell’s materials engineers are interested in protecting the metal parts the company manufactures from high humidity, temperature and industrial contaminants.
Aita’s unique nanolaminate coating is applied to the metal surface in ultra-thin layers, and together they adjust in response to a wide range of adverse conditions. The tiny crystals in the layers transform to surround and contain the defect.
Aita’s work has applications in a wide range of industries, including manufacturing, optical products and biomedical devices, an area in which she holds two patents.
Aita has an international reputation in the field of thin films for advanced materials and has been backed by some of the best-known companies in the area, including Johnson Controls, Badger Meter, Rockwell Automation, CERAC and Kohler.
Source: University of Wisconsin-Milwaukee
