Research on a new, more ecological system for painting airplanes
UC3M/DICYT Developing a new, more ecological system for painting airplanes, based on an experimental technique used in Materials Science. That is the objective of the European research project known as GreenGELAIR that began recently and in which scientists from Universidad Carlos III de Madrid (UC3M) are participating.
The researchers are designing a new formula, as well as a new application system, for paint coatings based on sol-gel technology that can be used in the aeronautical sector. The project’s main goal is to find a more ecological alternative to be used in the airplane painting process. Specifically, the researchers hope to develop a new, competitive sol-gel product along with a versatile system for applying it, for both maintenance operations and the manufacture of the aircraft’s original parts.
The GreenGELAIR project attempts to solve a problem posed by the paints that are currently used in various industries. These paints contain hexavalent chromium and, according to environmental regulations (REACH), must be substituted for others in the majority of sectors, particularly the aeronautics sector. To this end, Sol-gel technology is seen as one of the clean alternatives to coatings made up of chromium, according to the researchers. “The proposed sol-gel system will be versatile and competitive,” they state, “minimizing maintenance operations and costs, and eliminating the environmental problems raised by the current systems.” They point out that the project’s results can be applied in sectors other than aeronautics that use similar surface treatments.
With sol-gel technology, which is based on molecules composed of oxygen, silicon, hydrogen and carbon, certain chemical reactions are produced. These reactions lead to the formation of a polymeric coating network that can contain ecologically acceptable corrosion inhibitors. “When applied correctly, they form continuous, homogenous coatings that create an adequate barrier to corrosion even in extreme conditions,” they note. This technology offers additional advantages, such as the fact that non-toxic solvents can be used and that work can be carried out at normal room temperature.
In search of a clean sky
The project, which was begun in October of 2013, is expected to last two years. During that period, the scientists will complete the formulation and kinetic study of the project, as well as designing and constructing an application device and testing its efficacy on complex parts. In order to validate the product, different tests of the sol-gel system’s properties of adherence and protection against corrosion will be carried out in a variety of settings: large surfaces, small retouches, complete pieces and patches of fuselage. The researchers in UC3M’s Grupo de Tecnología de Polvos (Powder Technology Group) who are taking part in this initiative are going to be in charge of the “design and preparation of these new coatings in the laboratory in order to then analyze their resistance to corrosion,” explains Professor Antonia Jiménez Morales, of the Department of Materials Science and Engineering at UC3M.
The GreenGELAIR project was approved in the first call for proposals of CleanSky 2013, part of the 7th European Framework Program. This Joint Technological Initiative is a research project that is funded by the European Commission and the continent’s aeronautical industry, with the goal of creating a sustainable air space and reducing aviation’s environmental impact. The consortium for this project stands out due to its broad regional distribution within Spain: UC3M is participating as a technological partner with expertise in the development of sol-gel products that increase the adherence of paint to metallic substrates; the firm GALVATEC, which is located in Seville, is a partner with expertise in aerospace sector operations, both maintenance operations and the manufacture of original parts; and the Instituto Tecnológico Metalmecánico (AIMME – Metalmechanic Technological Institute) of the Autonomous Community of Valencia, is acting as the coordinator of the consortium, promoted by the French company Dassault Aviation.