Virginia Tech mechanical engineer develops new low-cost material coating technique
Ever stop to consider why lotus plant leaves always look clean? The hydrophobic – water repelling – characteristic of the leaf, termed the “Lotus effect,” helps the plant survive in muddy swamps, repelling dirt and producing beautiful flowers.
Of late, engineers have been paying more and more attention to nature’s efficiencies, such as the Lotus effect, and studying its behavior in order to make advances in technology. As one example, learning more about swarming schools of fish is aiding in the development of unmanned underwater vehicles. Other researchers are observing the extraordinary navigational abilities of bats that might lead to new ways to reconfigure aviation highways in the skies.
Ranga Pitchumani , professor of mechanical engineering at Virginia Tech and currently on an invitational assignment as the chief scientist and director of the Concentrating Solar Power and Systems Integration programs of the U.S. Department of Energy’s SunShot Initiative www.solar.energy.gov, would like to see more efficiencies and clever designs in technology. His work reflects this philosophy.
His recent development of a type of coating for materials that has little to no affinity for water emulates the Lotus effect. Commonplace material coatings are as simple as paints and varnishes. More sophisticated coatings might be used for resistance to corrosion, fire, or explosives.
The American Chemical Society recognized the impact of the work of Pitchumani and Atieh Haghdoost, a recent doctoral graduate from Pitchumani’s Advanced Materials and Technologies Laboratory (www.me.vt.edu/amtl), featuring their research on the cover of its April 15 issue of the publication Langmuir, a highly-cited, peer reviewed journal. The article can be found at: http://pubs.acs.org/doi/abs/10.1021/la403509d, which includes a video demonstration of the coating
Using a two-step technique, “We produced a low-cost and simple approach for coating metallic surfaces with an enduring superhydrophobic (strong water repellant) film of copper,” Pitchumani explained. Copper allows for high heat and electrical conductivity, and is the material of choice in many engineering applications such as heat exchangers and electronic circuit boards.
Numerous methods currently exist to produce coating surfaces that for all practical purposes do not get wet as the water droplets run off the material. A few examples are: spraying; self-assembly where molecules spontaneously organize themselves into a structure; and laser etching.
But Pitchumani and Haghdoost explained their method “differs in that their two-step process is used to directly make superhydrophobic copper coatings without the more costly need for an additional layer of a low surface energy material.”
The two-step process uses a common coating technique called electrodeposition. Again, they have a distinction – the difference from previous manufacturing practices is that Pitchumani and Haghdoost do not use a template that can adversely affect the texture of the coating that is deposited on the surface of the material or substrate. Their template-free process allows the coating material to be made of the same material as the substrate, thereby preserving its thermal and electrical properties.
The possibilities for the technology are huge. The coatings can minimize or eliminate “fouling” – dirt and grime accumulation – in heat exchangers, reduce pressure drop in flow through tubes, provide improved corrosion resistance, and mitigate creep failure in electronic printed circuit board applications. They currently have an international patent pending (PCT/US2014/016312), that was filed through the Virginia Tech Intellectual Property office.
In the future, they hope to expand the nature-inspired innovation to materials other than copper.
Lynn Nystrom | newswise
Dresdner scientists print tomorrow’s world
08.02.2017 | Fraunhofer-Institut für Werkstoff- und Strahltechnik IWS
New technology for mass-production of complex molded composite components
23.01.2017 | Evonik Industries AG
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
23.03.2017 | Life Sciences
23.03.2017 | Power and Electrical Engineering
23.03.2017 | Earth Sciences