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
New process for cell transfection in high-throughput screening
21.03.2016 | Laser Zentrum Hannover e.V.
Sustainable products: Fraunhofer LBF investigates recycling of halogen-free flame retardant
17.02.2016 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
A biological and energy-efficient process, developed and patented by the University of Innsbruck, converts nitrogen compounds in wastewater treatment facilities into harmless atmospheric nitrogen gas. This innovative technology is now being refined and marketed jointly with the United States’ DC Water and Sewer Authority (DC Water). The largest DEMON®-system in a wastewater treatment plant is currently being built in Washington, DC.
The DEMON®-system was developed and patented by the University of Innsbruck 11 years ago. Today this successful technology has been implemented in about 70...
Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.
The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...
In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.
In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...
Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices
Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.
When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene
In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...
24.05.2016 | Event News
20.05.2016 | Event News
19.05.2016 | Event News
27.05.2016 | Awards Funding
27.05.2016 | Life Sciences
27.05.2016 | Life Sciences