Engineers have developed a technique to make composite materials stiffer and stronger when exposed to ultraviolet light, according to a study conducted on April 17, 2018.
This study was conducted by engineers at the U.S. Army Research Laboratory and the University of Maryland. This on-demand control of composite behavior will help in enabling a variety of new capabilities for future Army rotorcraft design, performance, and maintenance.
According to the researchers, the main objective was to control the interaction of molecules with each other. A reduction in maintenance burden is one of the most important capabilities envisioned by these concepts. The results of the study shows that these composite materials could be made 93-percent stiffer and 35-percent stronger on exposure to ultraviolet light. In this method, the ultraviolet light reactive molecules are attached to the reinforcing agents like carbon nanotubes. They are then embedded in a polymer. On exposure to UV light, a chemical reaction occurs and the interaction between the reinforcing agents and the polymer increases, thereby making the material stiffer and stronger.
Researchers say that the chemistry used here can be applied to a variety of reinforcement/polymer combinations and thus, expands the utility of this control method to a wide range of material systems. Dr. Zhongjie Huang, a postdoctoral research fellow at the University of Maryland said, “This research shows that it is possible to control the overall material property of these nanocomposites through molecular engineering at the interface between the composite components. This is not only important for fundamental science but also for the optimization of structural component response.”
Design that correspond to lower mechanical loads and vibration are not achievable at present due to the limitations in structural damping in hingeless blade or wing structures. Furthermore, adaptive aerospace structures that could potentially accommodate mechanical loading conditions can be developed with the help of controllable mechanical response.